in one module but is only declared as a friend in another module, keep it
visible in the result of the merge.
This is incomplete on two axes:
1) Our handling of local extern declarations is basically broken (we put them
in the wrong decl context, and don't find them in redeclaration lookup, unless
they've previously been declared), and this results in them making friends
visible after a merge.
2) Eventually we'll need to mark that this has happened, and more carefully
check whether a declaration should be visible if it was only visible in some
of the modules in which it was declared. Fortunately it's rare for the
identifier namespace of a declaration to change along its redeclaration chain.
llvm-svn: 187639
sufficient to only consider names visible at the point of instantiation,
because that may not include names that were visible when the template was
defined. More generally, if the instantiation backtrace goes through a module
M, then every declaration visible within M should be available to the
instantiation. Any of those declarations might be part of the interface that M
intended to export to a template that it instantiates.
The fix here has two parts:
1) If we find a non-visible declaration during name lookup during template
instantiation, check whether the declaration was visible from the defining
module of all entities on the active template instantiation stack. The defining
module is not the owning module in all cases: we look at the module in which a
template was defined, not the module in which it was first instantiated.
2) Perform pending instantiations at the end of a module, not at the end of the
translation unit. This is general goodness, since it significantly cuts down
the amount of redundant work that is performed in every TU importing a module,
and also implicitly adds the module containing the point of instantiation to
the set of modules checked for declarations in a lookup within a template
instantiation.
There's a known issue here with template instantiations performed while
building a module, if additional imports are added later on. I'll fix that
in a subsequent commit.
llvm-svn: 187167
global allocation or deallocation function, that should not cause that global
allocation or deallocation function to become unavailable.
llvm-svn: 186270
numbers as we deserialize class template partial specializations. We can't
assume that the old sequence numbers will work.
The sequence numbers are still deterministic, but are now a lot less
predictable for class template partial specializations in modules/PCH.
llvm-svn: 184811
constructing a lookup table.
Previously, buildLookup would add lookup table entries for each item lexically
within the DC, and adding the first entry with a given name would trigger the
external source to add all its entries with that name. Then buildLookup would
carry on and re-add those entries all over again.
Instead, follow a simple rule: a declaration from an external source is only
ever made visible by the external source. One exception to this: since we don't
usually build a lookup table for the TU in C, and we never serialize one, we
don't expect the external source to provide lookups in the TU in C, so we build
those ones ourselves.
llvm-svn: 184696
As an optimization, we only kept declared methods with distinct
signatures in the global method pool, to keep the method lists
small. Under modules, however, one could have two different methods
with the same signature that occur in different (sub)modules. If only
the later submodule is important, message sends to 'id' with that
selector would fail because the first method (the only one that got
into the method pool) was hidden. When building a module, keep *all*
of the declared methods.
I did a quick check of both module build time and uses of modules, and
found no performance regression despite this causing us to keep more
methods in the global method pool. Fixes <rdar://problem/14148896>.
llvm-svn: 184504
Clang has an issue between mingw/include/float.h and clang/Headers/float.h with cyclic include_next.
For now, it should work to suppress #include_next in clang/float.h with an explicit target.
(It may work with -U__MINGW32__, though.)
llvm-svn: 181988
found for a receiver, note where receiver class
is declaraed (this is most common when receiver is a forward
class). // rdar://3258331
llvm-svn: 181847
After r180934 we may initiate module map parsing for modules not related to the module what we are building,
make sure we ignore the header file info of headers from such modules.
First part of rdar://13840148
llvm-svn: 181489
Summary:
Most of this change is wiring the pragma all the way through from the
lexer, parser, and sema to codegen. I considered adding a Decl AST node
for this, but it seemed too heavyweight.
Mach-O already uses a metadata flag called "Linker Options" to do this
kind of auto-linking. This change follows that pattern.
LLVM knows how to forward the "Linker Options" metadata into the COFF
.drectve section where these flags belong. ELF support is not
implemented, but possible.
This is related to auto-linking, which is http://llvm.org/PR13016.
CC: cfe-commits
Differential Revision: http://llvm-reviews.chandlerc.com/D723
llvm-svn: 181426
Previously, we would clone the current diagnostic consumer to produce
a new diagnostic consumer to use when building a module. The problem
here is that we end up losing diagnostics for important diagnostic
consumers, such as serialized diagnostics (where we'd end up with two
diagnostic consumers writing the same output file). With forwarding,
the diagnostics from all of the different modules being built get
forwarded to the one serialized-diagnostic consumer and are emitted in
a sane way.
Fixes <rdar://problem/13663996>.
llvm-svn: 181067
The "magical" builtin headers are the headers we provide as part of
the C standard library, which typically comes from /usr/include. We
essentially merge our headers into that location (due to cyclic
dependencies). This change makes sure that, when header search finds
one of our builtin headers, we figure out which module it actually
lives in. This case is fairly rare; one ends up having to include one
of the few built-in C headers we provide before including anything
from /usr/include to trigger it. Fixes <rdar://problem/13787184>.
llvm-svn: 180934
-Make sure that a deserialized external decl gets added to the TU scope.
-When associating an identifier with a set of decls, use the most recent local ones,
if they exist, otherwise associating decls from modules (that came after a local one)
will lead to an incomplete reconstructed re-declaration chain.
rdar://13712705
llvm-svn: 180634
Microsoft's Source Annotation Language (SAL) defines a bunch of keywords
for annotating the inputs and outputs of functions. Empty definitions
for the keywords are provided by <stdlib.h> -> <crtdefs.h> -> <sal.h>.
This makes it basically impossible to include MSVC's stdlib.h and
Clang's *mmintrin.h headers at the same time if they have variables
named __in. As a workaround, I've renamed those variables.
This fixes the Modules/compiler_builtins.m test which was XFAILed,
presumably due to this conflict.
llvm-svn: 179860
VerifyDiagnosticConsumer previously would not check that the diagnostic and
its matching directive referenced the same source file. Common practice was
to create directives that referenced other files but only by line number,
and this led to problems such as when the file containing the directive
didn't have enough lines to match the location of the diagnostic in the
other file, leading to bizarre file formatting and other oddities.
This patch causes VerifyDiagnosticConsumer to match source files as well as
line numbers. Therefore, a new syntax is made available for directives, for
example:
// expected-error@file:line {{diagnostic message}}
This extends the @line feature where "file" is the file where the diagnostic
is generated. The @line syntax is still available and uses the current file
for the diagnostic. "file" can be specified either as a relative or absolute
path - although the latter has less usefulness, I think! The #include search
paths will be used to locate the file and if it is not found an error will be
generated.
The new check is not optional: if the directive is in a different file to the
diagnostic, the file must be specified. Therefore, a number of test-cases
have been updated with regard to this.
This closes out PR15613.
llvm-svn: 179677
- There is no reason to have a modules specific flag for disabling
autolinking. Instead, convert the existing flag into -fno-autolink (which
should cover other autolinking code generation paths like #pragmas if and
when we support them).
llvm-svn: 179612
This is a Darwin-SDK-specific hash criteria used to identify a
particular SDK without having to hash the contents of all of its
headers. If other platforms have such versioned files, we should add
those checks here.
llvm-svn: 179346
Normal name lookup ignores any hidden declarations. When name lookup
for builtin declarations fails, we just synthesize a new
declaration at the point of use. With modules, this could lead to
multiple declarations of the same builtin, if one came from a (hidden)
submodule that was later made visible. Teach name lookup to always
find builtin names, so we don't create these redundant declarations in
the first place.
llvm-svn: 178711
Syntactically means the function macro parameter names do not need to use the same
identifiers in order for the definitions to be considered identical.
Syntactic equivalence is a microsoft extension for macro redefinitions and we'll also
use this kind of comparison to check for ambiguous macros coming from modules.
rdar://13562254
llvm-svn: 178671
This option can be useful for end users who want to know why they
ended up with a ton of different variants of the "std" module in their
module cache. This problem should go away over time, as we reduce the
need for module variants, but it will never go away entirely.
llvm-svn: 178148
Also update "test/Modules/macros.c" to test modified semantics:
-When there is an ambiguous macro, expand using the latest introduced version, not the first one.
-#undefs in submodules cause the macro to not be exported by that submodule, it doesn't cause
undefining of macros in the translation unit that imported that submodule.
This reduces macro namespace interference across modules.
llvm-svn: 178105
Clang's <stddef.h> provides definitions for the C standard library
types size_t, ptrdiff_t, and wchar_t. However, the system's C standard
library headers tend to provide the same typedefs, and the two
generally avoid each other using the macros
_SIZE_T/_PTRDIFF_T/_WCHAR_T. With modules, however, we need to see
*all* of the places where these types are defined, so provide the
typedefs (ignoring the macros) when modules are enabled.
llvm-svn: 177686
We now put the Clang module cache in
<system-temp-directory>/org.llvm.clang/ModuleCache. Perhaps some day
there will be other caches under <system-temp-directory>/org.llvm.clang>.
llvm-svn: 177671
Configuration macros are macros that are intended to alter how a
module works, such that we need to build different module variants
for different values of these macros. A module can declare its
configuration macros, in which case we will complain if the definition
of a configation macro on the command line (or lack thereof) differs
from the current preprocessor state at the point where the module is
imported. This should eliminate some surprises when enabling modules,
because "#define CONFIG_MACRO ..." followed by "#include
<module/header.h>" would silently ignore the CONFIG_MACRO setting. At
least it will no longer be silent about it.
Configuration macros are eventually intended to help reduce the number
of module variants that need to be built. When the list of
configuration macros for a module is exhaustive, we only need to
consider the settings for those macros when building/finding the
module, which can help isolate modules for various project-specific -D
flags that should never affect how modules are build (but currently do).
llvm-svn: 177466
The global module index was querying the file manager for each of the
module files it knows about at load time, to prune out any out-of-date
information. The file manager would then cache the results of the
stat() falls used to find that module file.
Later, the same translation unit could end up trying to import one of the
module files that had previously been ignored by the module cache, but
after some other Clang instance rebuilt the module file to bring it
up-to-date. The stale stat() results in the file manager would
trigger a second rebuild of the already-up-to-date module, causing
failures down the line.
The global module index now lazily resolves its module file references
to actual AST reader module files only after the module file has been
loaded, eliminating the stat-caching race. Moreover, the AST reader
can communicate to its caller that a module file is missing (rather
than simply being out-of-date), allowing us to simplify the
module-loading logic and allowing the compiler to recover if a
dependent module file ends up getting deleted.
llvm-svn: 177367
This commit introduces a set of related changes to ensure that the
declaration that shows up in the identifier chain after deserializing
declarations with a given identifier is, in fact, the most recent
declaration. The primary change involves waiting until after we
deserialize and wire up redeclaration chains before updating the
identifier chains. There is a minor optimization in here to avoid
recursively deserializing names as part of looking to see whether
top-level declarations for a given name exist.
A related change that became suddenly more urgent is to property
record a merged declaration when an entity first declared in the
current translation unit is later deserialized from a module (that had
not been loaded at the time of the original declaration). Since we key
off the canonical declaration (which is parsed, not from an AST file)
for emitted redeclarations, we simply record this as a merged
declaration during AST writing and let the readers merge them.
Re-fixes <rdar://problem/13189985>, presumably for good this time.
llvm-svn: 175447
the linkage of functions and variables while merging declarations from modules,
and we don't necessarily have enough of the rest of the AST loaded at that
point to allow us to compute linkage, so serialize it instead.
llvm-svn: 174943
lexical storage but not visible storage' case in C++. It's unclear whether we
even need the special-case handling for C++, since it seems to be working
around our not serializing a lookup table for the TU in C. But in any case,
the assertion is incorrect.
llvm-svn: 174931
These two related tweaks to keep the information associated with a
given identifier correct when the identifier has been given some
top-level information (say, a top-level declaration) and more
information is then loaded from a module. The first ensures that an
identifier that was "interesting" before being loaded from an AST is
considered to be different from its on-disk counterpart. Otherwise, we
lose such changes when writing the current translation unit as a
module.
Second, teach the code that injects AST-loaded names into the
identifier chain for name lookup to keep the most recent declaration,
so that we don't end up confusing our declaration chains by having a
different declaration in there.
llvm-svn: 174895
visible.
The basic problem here is that a given translation unit can use
forward declarations to form pointers to a given type, say,
class X;
X *x;
and then import a module that includes a definition of X:
import XDef;
We will then fail when attempting to access a member of X, e.g.,
x->method()
because the AST reader did not know to look for a default of a class
named X within the new module.
This implementation is a bit of a C-centric hack, because the only
definitions that can have this property are enums, structs, unions,
Objective-C classes, and Objective-C protocols, and all of those are
either visible at the top-level or can't be defined later. Hence, we
can use the out-of-date-ness of the name and the identifier-update
mechanism to force the update.
In C++, we will not be so lucky, and will need a more advanced
solution, because the definitions could be in namespaces defined in
two different modules, e.g.,
// module 1
namespace N { struct X; }
// module 2
namespace N { struct X { /* ... */ }; }
One possible implementation here is for C++ to extend the information
associated with each identifier table to include the declaration IDs
of any definitions associated with that name, regardless of
context. We would have to eagerly load those definitions.
llvm-svn: 174794
included in the same test. Clang gets confused about whether it's already built
a module for this file, when running on a content-addressible filesystem.
llvm-svn: 174694
overloads of a name by claiming that there are no lookup results for that name
in modules while loading the names from the module. Lookups in deserialization
really don't want to find names which they themselves are in the process of
introducing. This also has the pleasant side-effect of automatically caching
PCH lookups which found no names.
The runtime here is still quadratic in the number of overloads, but the
constant is lower.
llvm-svn: 174685
name lookup has been performed in that context (this probably only happens in
C++).
1) Whenever we add names to a context, set a flag on it, and if we perform
lookup and discover that the context has had a lookup table built but has the
flag set, update all entries in the lookup table with additional names from
the external source.
2) When marking a DeclContext as having external visible decls, mark the
context in which lookup is performed, not the one we are adding. These won't
be the same if we're adding another copy of a pre-existing namespace.
llvm-svn: 174577
The use of this flag enables a modules optimization where a given set
of macros can be labeled as "ignored" by the modules
system. Definitions of those macros will be completely ignored when
building the module hash and will be stripped when actually building
modules. The overall effect is that this flag can be used to
drastically reduce the number of
Eventually, we'll want modules to tell us what set of macros they
respond to (the "configuration macros"), and anything not in that set
will be excluded. However, that requires a lot of per-module
information that must be accurate, whereas this option can be used
more readily.
Fixes the rest of <rdar://problem/13165109>.
llvm-svn: 174560
This can happen when one abuses precompiled headers by passing more -D
options when using a precompiled hedaer than when it was built. This
is intentionally permitted by precompiled headers (and is exploited by
some build environments), but causes problems for modules.
First part of <rdar://problem/13165109>, detecting when something when
horribly wrong.
llvm-svn: 174554
Different modules may have different views of the various "special"
types in the AST, such as the redefinition type for "id". Merge those
types rather than only considering the redefinition types for the
first AST file loaded.
llvm-svn: 174234
-fno-modules-global-index -cc1 option to allow one to disable the
index for performance testing purposes, but with a 10% win in
-fsyntax-only time, there is no reason a user would do this.
llvm-svn: 173707
AST reader.
The global module index tracks all of the identifiers known to a set
of module files. Lookup of those identifiers looks first in the global
module index, which returns the set of module files in which that
identifier can be found. The AST reader only needs to look into those
module files and any module files not known to the global index (e.g.,
because they were (re)built after the global index), reducing the
number of on-disk hash tables to visit. For an example source I'm
looking at, we go from 237844 total identifier lookups into on-disk
hash tables down to 126817.
Unfortunately, this does not translate into a performance advantage.
At best, it's a wash once the global module index has been built, but
that's ignore the cost of building the global module index (which
is itself fairly large). Profiles show that the global module index
code is far less efficient than it should be; optimizing it might give
enough of an advantage to justify its continued inclusion.
llvm-svn: 173405
The global module index is a "global" index for all of the module
files within a particular subdirectory in the module cache, which
keeps track of all of the "interesting" identifiers and selectors
known in each of the module files. One can perform a fast lookup in
the index to determine which module files will have more information
about entities with a particular name/selector. This information can
help eliminate redundant lookups into module files (a serious
performance problem) and help with creating auto-import/auto-include
Fix-Its.
The global module index is created or updated at the end of a
translation unit that has triggered a (re)build of a module by
scraping all of the .pcm files out of the module cache subdirectory,
so it catches everything. As with module rebuilds, we use the file
system's atomicity to synchronize.
llvm-svn: 173301
that redefined a macro without undef'ing it first.
Proper reconstruction of the macro info history from modules will properly fix this in subsequent commits.
rdar://13016031
llvm-svn: 173281
consider (sub)module visibility.
The bulk of this change replaces myriad hand-rolled loops over the
linked list of Objective-C categories/extensions attached to an
interface declaration with loops using one of the four new category
iterator kinds:
visible_categories_iterator: Iterates over all visible categories
and extensions, hiding any that have their "hidden" bit set. This is
by far the most commonly used iterator.
known_categories_iterator: Iterates over all categories and
extensions, ignoring the "hidden" bit. This tends to be used for
redeclaration-like traversals.
visible_extensions_iterator: Iterates over all visible extensions,
hiding any that have their "hidden" bit set.
known_extensions_iterator: Iterates over all extensions, whether
they are visible to normal name lookup or not.
The effect of this change is that any uses of the visible_ iterators
will respect module-import visibility. See the new tests for examples.
Note that the old accessors for categories and extensions are gone;
there are *Raw() forms for some of them, for those (few) areas of the
compiler that have to manipulate the linked list of categories
directly. This is generally discouraged.
Part two of <rdar://problem/10634711>.
llvm-svn: 172665
!0 = metadata !{metadata !"-lautolink"}
!1 = metadata !{metadata !"-framework", metadata !"autolink_framework"}
referenced from llvm.module.linkoptions, e.g.,
!llvm.module.linkoptions = !{!0, !1, !2, !3}
This conceptually moves the logic for figuring out the syntax the
linker will accept from LLVM into Clang. Moreover, it makes it easier
to support MSVC's
#pragma comment(linker, "some option")
in the future, should anyone care to do so.
llvm-svn: 172441
will have a shared library with the same name as its framework (and no
suffix!) within its .framework directory. Detect this both when
inferring the whole top-level framework and when parsing a module map.
llvm-svn: 172439
metadata for linking against the libraries/frameworks for imported
modules.
The module map language is extended with a new "link" directive that
specifies what library or framework to link against when a module is
imported, e.g.,
link "clangAST"
or
link framework "MyFramework"
Importing the corresponding module (or any of its submodules) will
eventually link against the named library/framework.
For now, I've added some placeholder global metadata that encodes the
imported libraries/frameworks, so that we can test that this
information gets through to the IR. The format of the data is still
under discussion.
llvm-svn: 172437
which a particular declaration resides. Use this information to
customize the "definition of 'blah' must be imported from another
module" diagnostic with the module the user actually has to
import. Additionally, recover by importing that module, so we don't
complain about other names in that module.
Still TODO: coming up with decent Fix-Its for these cases, and expand
this recovery approach for other name lookup failures.
llvm-svn: 172290
(because they are part of some module) but have not been made visible
(because they are in a submodule that wasn't imported), filter out
those declarations unless both the old declaration and the new
declaration have external linkage. When one or both has internal
linkage, there should be no conflict unless both are imported.
llvm-svn: 171925
RUN: a
RUN: b || true
lit expands it to a && b || true, and the || true applies to both commands (thus ignoring failures in 'a')! This is PR10867 again.
llvm-svn: 169434
state so that all of the various clones end up rendering their
diagnostics into the same serialized-diagnostics file. This is
important when we actually want failures during module build to be
reported back to the translation unit that tried to import the
not-yet-built or out-of-date module. <rdar://problem/12565727>
llvm-svn: 169057
module, provide a module import stack similar to what we would get for
an include stack, e.g.,
In module 'DependsOnModule' imported from build-fail-notes.m:4:
In module 'Module' imported from DependsOnModule.framework/Headers/DependsOnModule.h:1:
Inputs/Module.framework/Headers/Module.h:15:12: note: previous definition is here
@interface Module
<rdar://problem/12696425>
llvm-svn: 169042
building module 'Foo' imported from..." notes (the same we we provide
"In file included from..." notes) in the diagnostic, so that we know
how this module got included in the first place. This is part of
<rdar://problem/12696425>.
llvm-svn: 169021
import of that module elsewhere, don't try to build the module again:
it won't work, and the experience is quite dreadful. We track this
information somewhat globally, shared among all of the related
CompilerInvocations used to build modules on-the-fly, so that a
particular Clang instance will only try to build a given module once.
Fixes <rdar://problem/12552849>.
llvm-svn: 168961
allowing a module map to be placed one level above the '.framework'
directories to specify that all .frameworks within that directory can
be inferred as framework modules. One can also specifically exclude
frameworks known not to work.
This makes explicit (and more restricted) behavior modules have had
"forever", where *any* .framework was assumed to be able to be built
as a module. That's not necessarily true, so we white-list directories
(with exclusions) when those directories have been audited.
llvm-svn: 167482
token. This is important because the first token could actually be
after an #include that triggers a module import, which might use
either Sema or the AST consumer before it would have been initialized.
llvm-svn: 167423
While we're here, extend the module map to cover most of the
newly-added instrinsic headers. Only wmmintrin.h is missing, because
it needs to be split into AES/PCLMUL subheaders (as a separate commit).
llvm-svn: 167398
description. Previously, one could emulate this behavior by placing
the header in an always-unavailable submodule, but Argyrios guilted me
into expressing this idea properly.
llvm-svn: 165921
macro history.
When deserializing macro history, we arrange history such that the
macros that have definitions (that haven't been #undef'd) and are
visible come at the beginning of the list, which is what the
preprocessor and other clients of Preprocessor::getMacroInfo()
expect. If additional macro definitions become visible later, they'll
be moved toward the front of the list. Note that it's possible to have
ambiguities, but we don't diagnose them yet.
There is a partially-implemented design decision here that, if a
particular identifier has been defined or #undef'd within the
translation unit, that definition (or #undef) hides any macro
definitions that come from imported modules. There's still a little
work to do to ensure that the right #undef'ing happens.
Additionally, we'll need to scope the update records for #undefs, so
they only kick in when the submodule containing that update record
becomes visible.
llvm-svn: 165682
MacroInfo*. Instead of simply dumping an offset into the current file,
give each macro definition a proper ID with all of the standard
modules-remapping facilities. Additionally, when a macro is modified
in a subsequent AST file (e.g., #undef'ing a macro loaded from another
module or from a precompiled header), provide a macro update record
rather than rewriting the entire macro definition. This gives us
greater consistency with the way we handle declarations, and ties
together macro definitions much more cleanly.
Note that we're still not actually deserializing macro history (we
never were), but it's far easy to do properly now.
llvm-svn: 165560
whether that function/method already has a body (loaded from some
other AST file), as introduced in r165137. Delay this check until
after the redeclaration chains have been wired up.
While I'm here, make the loading of method bodies lazy.
llvm-svn: 165513
This is especially relevant for templatedDecls that might be injected (and thus have their DeclContext set to) somewhere completely different.
llvm-svn: 165005
Check whether a pending instantiation needs to be instantiated (or whether an instantiation already exists).
Verify the size of the PendingInstantiations record (was only checking size of existing PendingInstantiations).
Migrate Obj-C++ part of redecl-merge into separate test, now that this is growing.
templates.mm: test that CodeGen has seen exactly one definition of template instantiations.
redecl-merge.m: use "@" specifier for expected-diagnostics.
llvm-svn: 164993
Lookup can nevertheless find them due to the serialized lookup table.
For instance when reading a template decl's templatedDecl, it will search for existing decls that it could be a redeclaration of, and find the half-read template decl.
Thus there is no point in asserting the names of decls.
llvm-svn: 164932
specific module (__building_module(modulename)) and to get the name of
the current module as an identifier (__MODULE__).
Used to help headers behave differently when they're being included as
part of building a module. Oh, the irony.
llvm-svn: 164605
statement starts with an identifier for which name lookup will fail either way,
look at later tokens to disambiguate in order to improve error recovery.
llvm-svn: 162464
The old behavior was to re-scan any files (like modules) where we may have
directives but won't actually be parsing during the -verify invocation.
Now, we keep the old behavior in Debug builds as a sanity check (though
modules are a known entity), and expect all legitimate directives to come
from comments seen by the preprocessor.
This also affects the ARC migration tool, which captures diagnostics in
order to filter some out. This change adds an explicit cleanup to
CaptureDiagnosticsConsumer in order to let its sub-consumer handle the
real end of diagnostics.
This was originally split into four patches, but the tests do not run
cleanly without all four, so I've combined them into one commit.
Patches by Andy Gibbs, with slight modifications from me.
llvm-svn: 161650
This is accomplished by making VerifyDiagnosticsConsumer a CommentHandler,
which then only reads the -verify directives that are actually in live
blocks of code. It also makes it simpler to handle -verify directives that
appear in header files, though we still have to manually reparse some files
depending on how they are generated.
This requires some test changes. In particular, all PCH tests now have their
-verify directives outside the "header" portion of the file, using the @line
syntax added in r159978. Other tests have been modified mostly to make it
clear what is being tested, and to prevent polluting the expected output with
the directives themselves.
Patch by Andy Gibbs! (with slight modifications)
The new Frontend/verify-* tests exercise the functionality of this commit,
as well as r159978, r159979, and r160053 (Andy's other -verify enhancements).
llvm-svn: 160068
turns out that it's actually needed for C++ modules support. Since simplifying
it didn't cause any test failures, I'll add a test for it.
llvm-svn: 154582
The warning this inhibits, -Wobjc-root-class, is opt-in for now. However, all clang unit tests that would trigger
the warning have been updated to use -Wno-objc-root-class. <rdar://problem/7446698>
llvm-svn: 154187
The deferred lookup table building step couldn't accurately tell which Decls
should be included in the lookup table, and consequently built different tables
in some cases.
Fix this by removing lazy building of DeclContext name lookup tables. In
practice, the laziness was frequently not worthwhile in C++, because we
performed lookup into most DeclContexts. In C, it had a bit more value,
since there is no qualified lookup.
In the place of lazy lookup table building, we simply don't build lookup tables
for function DeclContexts at all. Such name lookup tables are not useful, since
they don't capture the scoping information required to correctly perform name
lookup in a function scope.
The resulting performance delta is within the noise on my testing, but appears
to be a very slight win for C++ and a very slight loss for C. The C performance
can probably be recovered (if it is a measurable problem) by avoiding building
the lookup table for the translation unit.
llvm-svn: 152608
into using non-absolute system includes (<foo>)...
... and introduce another hack that is simultaneously more heineous
and more effective. We whitelist Clang-supplied headers that augment
or override system headers (such as float.h, stdarg.h, and
tgmath.h). For these headers, Clang does not provide a module
mapping. Instead, a system-supplied module map can refer to these
headers in a system module, and Clang will look both in its own
include directory and wherever the system-supplied module map
suggests, then adds either or both headers. The end result is that
Clang-supplied headers get merged into the system-supplied module for
the C standard library.
As a drive-by, fix up a few dependencies in the _Builtin_instrinsics
module.
llvm-svn: 149611
On Cygwin, at first, <stddef.h> is included without __need_wint_t.
Next, <stddef.h> is included with __need_wint_t, though Modules feature would not process <stddef.h> twice.
Then, wint_t is not found in system headers.
llvm-svn: 149500
builds, and bring mm_alloc.h into the fold. Start playing some tricks
with these builtin modules to mirror the include_next tricks that the
headers already perform.
llvm-svn: 149434
each of the targets. Use this for module requirements, so that we can
pin the availability of certain modules to certain target features,
e.g., provide a module for xmmintrin.h only when SSE support is
available.
Use these feature names to provide a nearly-complete module map for
Clang's built-in headers. Only mm_alloc.h and unwind.h are missing,
and those two are fairly specialized at the moment. Finishes
<rdar://problem/10710060>.
llvm-svn: 149227
headers. The remaining headers require more sophisticated
requirements; they'll be handled separately. Part of
<rdar://problem/10710060>.
llvm-svn: 149206
single attribute ("system") that allows us to mark a module as being a
"system" module. Each of the headers that makes up a system module is
considered to be a system header, so that we (for example) suppress
warnings there.
If a module is being inferred for a framework, and that framework
directory is within a system frameworks directory, infer it as a
system framework.
llvm-svn: 149143
the direct serialization of the linked-list structure. Instead, use a
scheme similar to how we handle redeclarations, with redeclaration
lists on the side. This addresses several issues:
- In cases involving mixing and matching of many categories across
many modules, the linked-list structure would not be consistent
across different modules, and categories would get lost.
- If a module is loaded after the class definition and its other
categories have already been loaded, we wouldn't see any categories
in the newly-loaded module.
llvm-svn: 149112
additional data from the external Sema source. This properly copes
with modules that are imported after we have already searched in the
global method pool for a given selector. For PCH, it's a slight
pessimization to be fixed soon.
llvm-svn: 148891
protocol, record the definition pointer in the canonical declaration
for that entity, and then propagate that definition pointer from the
canonical declaration to all other deserialized declarations. This
approach works well even when deserializing declarations that didn't
know about the original definition, which can occur with modules.
A nice bonus from this definition-deserialization approach is that we
no longer need update records when a definition is added, because the
redeclaration chains ensure that the if any declaration is loaded, the
definition will also get loaded.
llvm-svn: 148223
framework is actually a subframework within a top-level framework. If
so, only infer a module for the top-level framework and then dig out
the appropriate submodule.
This helps us cope with an amusing subframeworks anti-pattern, where
one uses -F <framework>/Frameworks to get direct include access to the
subframeworks of a framework (which otherwise would not be
permitted).
llvm-svn: 148148
the anonymous namespace to its parent. Semantically, this means that
the anonymous namespaces defined in one module are distinct from the
anonymous namespaces defined in another module.
llvm-svn: 147782
modules. Teach name lookup into namespaces to search in each of the
merged DeclContexts as well as the (now-primary) DeclContext. This
supports the common case where two different modules put something
into the same namespace.
llvm-svn: 147778
is important because it's fairly common for headers (especially system
headers) to want to provide only those typedefs needed for that
particular header, based on some guard macro, e.g.,
#ifndef _SIZE_T
#define _SIZE_T
typedef long size_t;
#endif
which is repeated in a number of headers. The guard macro protects
against duplicate definitions. However, this means that only the first
occurrence of this pattern actually defines size_t, so the submodule
corresponding to this header has the only visible definition. If a
user then imports a different submodule from the same module, size_t
will be known but not visible, and therefore cannot be used.
By allowing redefinition of typedefs, each header that wants to define
size_t can do so independently, so it will be available in the
corresponding submodules.
llvm-svn: 147775
to Redeclarable<NamespaceDecl>, so that we benefit from the improveed
redeclaration deserialization and merging logic provided by
Redeclarable<T>. Otherwise, no functionality change.
As a drive-by fix, collapse the "inline" bit into the low bit of the
original namespace/anonymous namespace, saving 8 bytes per
NamespaceDecl on x86_64.
llvm-svn: 147729
include stack to find the first file that is known to be part of the
module. This copes with situations where the module map doesn't
completely specify all of the headers that are involved in the module,
which can come up when there are very strange #include_next chains
(e.g., with weird compiler/stdlib headers like stdarg.h or float.h).
llvm-svn: 147662
to see hidden declarations because every tag lookup is effectively a
redeclaration lookup. For example, image that
struct foo;
is declared in a submodule that is known but hasn't been imported. If
someone later writes
struct foo *foo_p;
then "struct foo" is either a reference or a redeclaration. To keep
the redeclaration chains sound, we treat it like a redeclaration for
name-lookup purposes.
llvm-svn: 147588
different modules. This implementation is a first approximation of
what we want, using only the function type to determine
equivalence. Later, we'll want to deal with some of the more subtle
issues, including:
- C allows a prototyped declaration and a non-prototyped declaration
to be merged, which we should support
- We may want to ignore the return type when merging, then
complain if the return types differ. Or, we may want to leave it
as it us, so that we only complain if overload resolution
eventually fails.
- C++ non-static member functions need to consider cv-qualifiers
and ref-qualifiers.
- Function templates need to consider the template parameters and
return type.
- Function template specializations will have special rules.
- We can now (accidentally!) end up overloading in C, even without
the "overloadable" attribute, and will need to detect this at some
point.
The actual detection of "is this an overload?" is implemented by
Sema::IsOverload(), which will need to be moved into the AST library
for re-use here. That will be a future refactor.
llvm-svn: 147534
the AST reader doesn't actually perform a merge, because name lookup
knows how to merge identical typedefs together.
As part of this, teach C/Objective-C name lookup to return multiple
results in all cases, rather than first digging through the attributes
to see if the value is overloadable. This way, we'll catch ambiguous
lookups in C/Objective-C.
llvm-svn: 147498
that if two modules A and B both contain a declaration of a tag such
as
struct X;
and those two modules are unrelated, the two declarations of X will be
merged into a single redeclaration chain.
llvm-svn: 147488
modules. This leaves us without an explicit syntax for importing
modules in C/C++, because such a syntax needs to be discussed
first. In Objective-C/Objective-C++, the @import syntax is used to
import modules.
Note that, under -fmodules, C/C++ programs can import modules via the
#include mechanism when a module map is in place for that header. This
allows us to work with modules in C/C++ without committing to a syntax.
llvm-svn: 147467
module imports from -fauto-module-import to -fmodules. The new name
will eventually be used to enable modules, and the #include/#import
mapping is a crucial part of the feature.
llvm-svn: 147447
features needed for a particular module to be available. This allows
mixed-language modules, where certain headers only work under some
language variants (e.g., in C++, std.tuple might only be available in
C++11 mode).
llvm-svn: 147387
found within that umbrella directory that were not actually included
by the umbrella header. They should either be referenced in the module
map or included by the umbrella header.
llvm-svn: 147207
set of (previously-canonical) declaration IDs to the module file, so
that future AST reader instances that load the module know which
declarations are merged. This is important in the fairly tricky case
where a declaration of an entity, e.g.,
@class X;
occurs before the import of a module that also declares that
entity. We merge the declarations, and record the fact that the
declaration of X loaded from the module was merged into the (now
canonical) declaration of X that we parsed.
llvm-svn: 147181
declaration of that same class that either came from some other module
or occurred in the translation unit loading the module. In this case,
we need to merge the two redeclaration chains immediately so that all
such declarations have the same canonical declaration in the resulting
AST (even though they don't in the module files we've imported).
Focusing on Objective-C classes until I'm happy with the design, then
I'll both (1) extend this notion to other kinds of declarations, and
(2) optimize away this extra checking when we're not dealing with
modules. For now, doing this checking for PCH files/preambles gives us
better testing coverage.
llvm-svn: 147123
visibility restrictions. This ensures that all declarations of the
same entity end up in the same redeclaration chain, even if some of
those declarations aren't visible. While this may seem unfortunate to
some---why can't two C modules have different functions named
'f'?---it's an acknowedgment that a module does not introduce a new
"namespace" of names.
As part of this, stop merging the 'module-private' bit from previous
declarations to later declarations, because we want each declaration
in a module to stand on its own because this can effect, for example,
submodule visibility.
Note that this notion of names that are invisible to normal name
lookup but are available for redeclaration lookups is how we should
implement friend declarations and extern declarations within local
function scopes. I'm not tackling that problem now.
llvm-svn: 146980
hitting a submodule that was never actually created, e.g., because
that header wasn't parsed. In such cases, complain (because the
module's umbrella headers don't cover everything) and fall back to
including the header.
Later, we'll add a warning at module-build time to catch all such
cases. However, this fallback is important to eliminate assertions in
the ASTWriter when this happens.
llvm-svn: 146933
with a definition pointer (e.g., C++ and Objective-C classes), zip
through the redeclaration chain to make sure that all of the
declarations point to the definition data.
As part of this, realized again why the first redeclaration of an
entity in a file is important, and brought back that idea.
llvm-svn: 146886
redeclaration templates (RedeclarableTemplateDecl), similarly to the
way (de-)serialization is implemented for Redeclarable<T>. In the
process, found a simpler formulation for handling redeclaration
chains and implemented that in both places.
The new test establishes that we're building the redeclaration chains
properly. However, the FIXME indicates where we're tickling a
different bug that has to do with us not setting the DefinitionData
pointer properly in redeclarations that we detected after the
definition itself was deserialized. The (separable) fix for that bug
is forthcoming.
llvm-svn: 146883
imported modules that don't introduce any new entities of a particular
kind. Allow these entries to be replaced with entries for another
loaded module.
In the included test case, selectors exhibit this behavior.
llvm-svn: 146870
which there are no redeclarations. This reduced by size of the PCH
file for Cocoa.h by ~650k: ~536k of that was in the new
LOCAL_REDECLARATIONS table, which went from a ridiculous 540k down to
an acceptable 3.5k, while the rest was due to the more compact
abbreviated representation of redeclarable declaration kinds (which no
longer need to store the 'first' declaration ID).
llvm-svn: 146869
chains. The previous implementation relied heavily on the declaration
chain being stored as a (circular) linked list on disk, as it is in
memory. However, when deserializing from multiple modules, the
different chains could get mixed up, leading to broken declaration chains.
The new solution keeps track of the first and last declarations in the
chain for each module file. When we load a declaration, we search all
of the module files for redeclarations of that declaration, then
splice together all of the lists into a coherent whole (along with any
redeclarations that were actually parsed).
As a drive-by fix, (de-)serialize the redeclaration chains of
TypedefNameDecls, which had somehow gotten missed previously. Add a
test of this serialization.
This new scheme creates a redeclaration table that is fairly large in
the PCH file (on the order of 400k for Cocoa.h's 12MB PCH file). The
table is mmap'd in and searched via a binary search, but it's still
quite large. A future tweak will eliminate entries for declarations
that have no redeclarations anywhere, and should
drastically reduce the size of this table.
llvm-svn: 146841
diagnostic message are compared. If either is a substring of the other, then
no error is given. This gives rise to an unexpected case:
// expect-error{{candidate function has different number of parameters}}
will match the following error messages from Clang:
candidate function has different number of parameters (expected 1 but has 2)
candidate function has different number of parameters
It will also match these other error messages:
candidate function
function has different number of parameters
number of parameters
This patch will change so that the verification string must be a substring of
the diagnostic message before accepting. Also, all the failing tests from this
change have been corrected. Some stats from this cleanup:
87 - removed extra spaces around verification strings
70 - wording updates to diagnostics
40 - extra leading or trailing characters (typos, unmatched parens or quotes)
35 - diagnostic level was included (error:, warning:, or note:)
18 - flag name put in the warning (-Wprotocol)
llvm-svn: 146619
all of the headers below that particular directory. Use umbrella
directories as a clean way to deal with (1) directories/frameworks
that don't have an umbrella header, but don't want to enumerate all of
their headers, and (2) PrivateHeaders, which we never want to
enumerate and want to keep separate from the main umbrella header.
This also eliminates a little more of the "magic" for private headers,
and frameworks in general.
llvm-svn: 146235
umbrella headers in the sense that all of the headers within that
directory (and eventually its subdirectories) are considered to be
part of the module with that umbrella directory. However, unlike
umbrella headers, which are expected to include all of the headers
within their subdirectories, Clang will automatically include all of
the headers it finds in the named subdirectory.
The intent here is to allow a module map to trivially turn a
subdirectory into a module, where the module's structure can mimic the
directory structure.
llvm-svn: 146165
a modifier for a header declarartion, e.g.,
umbrella header "headername"
Collapse the umbrella-handling code in the parser into the
header-handling code, so we don't duplicate the header-search logic.
llvm-svn: 146159
when we load a module map (module.map) from a directory, also load a
private module map (module_private.map) for that directory, if
present. That private module map can inject a new submodule that
captures private headers.
llvm-svn: 146012
most specific (sub)module based on the actual file we find, rather
than always importing the top-level module. This means
that #include'ing <Foo/Blah.h> should give us the submodule Foo.Blah.
llvm-svn: 145942
frameworks). A submodule can now be labeled as a "framework", and
header search will look into the appropriate Headers/PrivateHeaders
subdirectories for named headers.
llvm-svn: 145941
explicit submodules or umbrella headers from submodules. Instead,
build the entire module at once, and let the name-hiding mechanisms
hide the contents of explicit submodules at load time.
llvm-svn: 145940
to re-export anything that it imports. This opt-in feature makes a
module behave more like a header, because it can be used to re-export
the transitive closure of a (sub)module's dependencies.
llvm-svn: 145811
"main" files that import modules. When loading any of these kinds of
AST files, we make the modules that were imported visible into the
translation unit that loaded the PCH file or preamble.
llvm-svn: 145737
precompiled header. Previously, we were trying to gather predefines
buffers from all kinds of AST files (which doesn't make sense) and
were performing some validation when AST files were loaded as main
files.
With these tweaks, using PCH files that import modules no longer fails
immediately (due to mismatched predefines buffers). However, module
visibility is lost, so this feature does not yet work.
llvm-svn: 145709
only the macro definitions from visible (sub)modules will actually be
visible. This provides the same behavior for macros that r145640
provided for declarations.
llvm-svn: 145683
within module maps, which will (eventually) be used to re-export a
module from another module. There are still some pieces missing,
however.
llvm-svn: 145665
check whether the named submodules themselves are actually
valid, and drill down to the named submodule (although we don't do
anything with it yet). Perform typo correction on the submodule names
when possible.
llvm-svn: 145477
into a module. This module can either be loaded from a module map in
the framework directory (which isn't quite working yet) or inferred
from an umbrella header (which does work, and replaces the existing
hack).
llvm-svn: 144877
the umbrella header's directory and its subdirectories are part of the
module (that's why it's an umbrella). Make sure that these headers are
considered to be part of the module for lookup purposes.
llvm-svn: 144859
file in the source manager. This allows us to properly create and use
modules described by module map files without umbrella headers (or
with incompletely umbrella headers). More generally, we can actually
build a PCH file that makes use of file -> buffer remappings, which
could be useful in libclang in the future.
llvm-svn: 144830
header, create our own in-memory buffer to parse all of the
appropriate headers, and use that to build the module. This isn't
end-to-end testable yet; that's coming next.
llvm-svn: 144797
into a submodule. Submodules aren't actually supported anywhere else,
but we do parse them, so this verifies that we're at least seeing
through them properly.
llvm-svn: 144436
the module is described in one of the module maps in a search path or
in a subdirectory off the search path that has the same name as the
module we're looking for.
llvm-svn: 144433
map, so long as they have an umbrella header. This makes it possible
to introduce a module map + umbrella header for a given set of
headers, to turn it into a module.
There are two major deficiencies here: first, we don't go hunting for
module map files when we just see a module import (so we won't know
about the modules described therein). Second, we don't yet have a way
to build modules that don't have umbrella headers, or have incomplete
umbrella headers.
llvm-svn: 144424
the corresponding (top-level) modules. This isn't actually useful yet,
because we don't yet have a way to build modules out of module maps.
llvm-svn: 144410
Module map files provide a way to map between headers and modules, so
that we can layer a module system on top of existing headers without
changing those headers at all.
This commit introduces the module map file parser and the module map
that it generates, and wires up the module map file parser so that
we'll automatically find module map files as part of header
search. Note that we don't yet use the information stored in the
module map.
llvm-svn: 144402
AST file more lazy, so that we don't eagerly load that information for
all known identifiers each time a new AST file is loaded. The eager
reloading made some sense in the context of precompiled headers, since
very few identifiers were defined before PCH load time. With modules,
however, a huge amount of code can get parsed before we see an
@import, so laziness becomes important here.
The approach taken to make this information lazy is fairly simple:
when we load a new AST file, we mark all of the existing identifiers
as being out-of-date. Whenever we want to access information that may
come from an AST (e.g., whether the identifier has a macro definition,
or what top-level declarations have that name), we check the
out-of-date bit and, if it's set, ask the AST reader to update the
IdentifierInfo from the AST files. The update is a merge, and we now
take care to merge declarations before/after imports with declarations
from multiple imports.
The results of this optimization are fairly dramatic. On a small
application that brings in 14 non-trivial modules, this takes modules
from being > 3x slower than a "perfect" PCH file down to 30% slower
for a full rebuild. A partial rebuild (where the PCH file or modules
can be re-used) is down to 7% slower. Making the PCH file just a
little imperfect (e.g., adding two smallish modules used by a bunch of
.m files that aren't in the PCH file) tips the scales in favor of the
modules approach, with 24% faster partial rebuilds.
This is just a first step; the lazy scheme could possibly be improved
by adding versioning, so we don't search into modules we already
searched. Moreover, we'll need similar lazy schemes for all of the
other lookup data structures, such as DeclContexts.
llvm-svn: 143100
as part of the hash rather than ignoring them. This means we'll end up
building more module variants (overall), but it allows configuration
macros such as NDEBUG to work so long as they're specified via command
line. More to come in this space.
llvm-svn: 142187
the AST reader), merge that header file information with whatever
header file information we already have. Otherwise, we might forget
something we already knew (e.g., that the header was #import'd already).
llvm-svn: 139979
arbitrary amount of code. This forces us to stage the AST writer more
strictly, ensuring that we don't assign a declaration ID to a
declaration until after we're certain that no more modules will get
loaded.
llvm-svn: 139974
target triple to separate modules built under different
conditions. The hash is used to create a subdirectory in the module
cache path where other invocations of the compiler (with the same
version, language options, etc.) can find the precompiled modules.
llvm-svn: 139662
but there is a corresponding umbrella header in a framework, build the
module on-the-fly so it can be immediately loaded at the import
statement. This is very much proof-of-concept code, with details to be
fleshed out over time.
llvm-svn: 139558
where the compiler will look for module files. Eliminates the
egregious hack where we looked into the header search paths for
modules.
llvm-svn: 139538
include guards don't show up as macro definitions in every translation
unit that imports a module. Macro definitions can, however, be
exported with the intentionally-ugly #__export_macro__
directive. Implement this feature by not even bothering to serialize
non-exported macros to a module, because clients of that module need
not (should not) know that these macros even exist.
llvm-svn: 138943
The initial incentive was to fix a crash when PCH chaining categories
to an interface, but the fix was done in the "modules way" that I hear
is popular with the kids these days.
Each module stores the local chain of categories and we combine them
when the interface is loaded. We also warn if non-dependent modules
introduce duplicate named categories.
llvm-svn: 138926
existing practice with Python extension modules. Not that Python
extension modules should be using a double-underscored identifier
anyway, but...
llvm-svn: 138870
__import__ within the preprocessor, since the prior one foolishly
assumed that Preprocessor::Lex() was re-entrant. We now handle
__import__ at the top level (only), after macro expansion. This should
fix the buildbot failures.
llvm-svn: 138704
loads the named module. The syntax itself is intentionally hideous and
will be replaced at some later point with something more
palatable. For now, we're focusing on the semantics:
- Module imports are handled first by the preprocessor (to get macro
definitions) and then the same tokens are also handled by the parser
(to get declarations). If both happen (as in normal compilation),
the second one is redundant, because we currently have no way to
hide macros or declarations when loading a module. Chris gets credit
for this mad-but-workable scheme.
- The Preprocessor now holds on to a reference to a module loader,
which is responsible for loading named modules. CompilerInstance is
the only important module loader: it now knows how to create and
wire up an AST reader on demand to actually perform the module load.
- We search for modules in the include path, using the module name
with the suffix ".pcm" (precompiled module) for the file name. This
is a temporary hack; we hope to improve the situation in the
future.
llvm-svn: 138679
from the given source. -emit-module behaves similarly to -emit-pch,
except that Sema is somewhat more strict about the contents of
-emit-module. In the future, there are likely to be more interesting
differences.
llvm-svn: 138595
given selector, rather than walking the chain backwards. Teach its
visitor how to merge multiple result sets into a single result set,
combining the results of selector lookup in several different modules
into a single result set.
llvm-svn: 138556
which supports both pre-order and post-order traversal via a visitor
mechanism. Use this depth-first search with a post-order traversal to
give predictable ordering semantics when walking all of the lexical
declarations in the translation unit.
Eventually, module imports will occur in the source code rather than
at the beginning, and we'll have to revisit this walk.
llvm-svn: 138490
module DAG-based lookup scheme. This required some reshuffling, so
that each module stores its own mapping from DeclContexts to their
lexical and visible sets for those DeclContexts (rather than one big
"chain").
Overall, this allows simple qualified name lookup into the translation
unit to gather results from multiple modules, with the lookup results
in module B shadowing the lookup results in module A when B imports A.
Walking all of the lexical declarations in a module DAG is still a
mess; we'll end up walking the loaded module list backwards, which
works fine for chained PCH but doesn't make sense in a DAG. I'll
tackle this issue as a separate commit.
llvm-svn: 138463
different modules) more robust. It already handled (simple) merges of
the set of declarations attached to that identifier, so add a test
case that shows us getting two different declarations for the same
identifier (one struct, one function) from different modules, and are
able to use both of them.
llvm-svn: 138189
modules (those that no other module depends on) and performs a search
over all of the modules, visiting a new module only when all of the
modules that depend on it have already been visited. The visitor can
abort the search for all modules that a module depends on, which
allows us to minimize the number of lookups necessary when performing
a search.
Switch identifier lookup from a linear walk over the set of modules to
this module visitation operation. The behavior is the same for simple
PCH and chained PCH, but provides the proper search order for
modules. Verified with printf debugging, since we don't have enough in
place to actually test this.
llvm-svn: 138187
has already been loaded before allocating a new Module structure. If
the module has already been loaded (uniquing based on file name), then
just return the existing module rather than trying to load it again.
This allows us to load a DAG of modules. Introduce a simple test case
that forms a diamond-shaped module graph, and illustrates that a
source file importing the bottom of the diamond can see declarations
in all four of the modules that make up the diamond.
Note that this version moves the file-opening logic into the module
manager, rather than splitting it between the module manager and the
AST reader. More importantly, it properly handles the
weird-but-possibly-useful case of loading an AST file from "-".
llvm-svn: 138030
Teach ModuleManager::addModule() to check whether a particular module
has already been loaded before allocating a new Module structure. If
the module has already been loaded (uniquing based on file name), then
just return the existing module rather than trying to load it again.
This allows us to load a DAG of modules. Introduce a simple test case
that forms a diamond-shaped module graph, and illustrates that a
source file importing the bottom of the diamond can see declarations
in all four of the modules that make up the diamond.
llvm-svn: 137971
has already been loaded before allocating a new Module structure. If
the module has already been loaded (uniquing based on file name), then
just return the existing module rather than trying to load it again.
This allows us to load a DAG of modules. Introduce a simple test case
that forms a diamond-shaped module graph, and illustrates that a
source file importing the bottom of the diamond can see declarations
in all four of the modules that make up the diamond.
llvm-svn: 137925