constructors in the current lexical context even though name lookup
found them via some other context merged into the redecl chain.
This can only happen for implicit constructors which can only have the
name of the type of the current context, so we can fix this by simply
*always* merging those names first. This also has the advantage of
removing the walk of the current lexical context from the common case
when this is the only constructor name we need to deal with (implicit or
otherwise).
I've enhanced the tests to cover this case (and uncovered an unrelated
bug which I fixed in r233325).
llvm-svn: 233327
Clang was inserting these into a dense map. While it never iterated the
dense map during normal compilation, it did when emitting a module. Fix
this by using a standard MapVector to preserve the order in which we
encounter the late parsed templates.
I suspect this still isn't ideal, as we don't seem to remove things from
this map even when we mark the templates as no longer late parsed. But
I don't know enough about this particular extension to craft a nice,
subtle test case covering this. I've managed to get the stress test to
at least do some late parsing and demonstrate the core problem here.
This patch fixes the test and provides deterministic behavior which is
a strict improvement over the prior state.
I've cleaned up some of the code here as well to be explicit about
inserting when that is what is actually going on.
llvm-svn: 233264
templates. Turns out all of this works correctly (so far). But it should
cover more code paths and will let me test some things that don't
actually work next.
llvm-svn: 233263
deterministically.
This fixes a latent issue where even Clang's Sema (and diagnostics) were
non-deterministic in the face of this pragma. The fix is super simple --
just use a MapVector so we track the order in which these are parsed (or
imported). Especially considering how rare they are, this seems like the
perfect tradeoff. I've also simplified the client code with judicious
use of auto and range based for loops.
I've added some pretty hilarious code to my stress test which now
survives the binary diff without issue.
llvm-svn: 233261
updated decl contexts get emitted.
Since this code was added, we have newer vastly simpler code for
handling this. The code I'm removing was very expensive and also
generated unstable order of declarations which made module outputs
non-deterministic.
All of the tests continue to pass for me and I'm able to check the
difference between the .pcm files after merging modules together.
llvm-svn: 233251
non-visible definition, skip the new definition and make the old one visible
instead of trying to parse it again and failing horribly. C++'s ODR allows
us to assume that the two definitions are identical.
llvm-svn: 233250
decl context lookup tables.
The first attepmt at this caused problems. We had significantly more
sources of non-determinism that I realized at first, and my change
essentially turned them from non-deterministic output into
use-after-free. Except that they weren't necessarily caught by tools
because the data wasn't really freed.
The new approach is much simpler. The first big simplification is to
inline the "visit" code and handle this directly. That works much
better, and I'll try to go and clean up the other caller of the visit
logic similarly.
The second key to the entire approach is that we need to *only* collect
names into a stable order at first. We then need to issue all of the
actual 'lookup()' calls in the stable order of the names so that we load
external results in a stable order. Once we have loaded all the results,
the table of results will stop being invalidated and we can walk all of
the names again and use the cheap 'noload_lookup()' method to quickly
get the results and serialize them.
To handle constructors and conversion functions (whose names can't be
stably ordered) in this approach, what we do is record only the visible
constructor and conversion function names at first. Then, if we have
any, we walk the decls of the class and add those names in the order
they occur in the AST. The rest falls out naturally.
This actually ends up simpler than the previous approach and seems much
more robust.
It uncovered a latent issue where we were building on-disk hash tables
for lookup results when the context was a linkage spec! This happened to
dodge all of the assert by some miracle. Instead, add a proper predicate
to the DeclContext class and use that which tests both for function
contexts and linkage specs.
It also uncovered PR23030 where we are forming somewhat bizarre negative
lookup results. I've just worked around this with a FIXME in place
because fixing this particular Clang bug seems quite hard.
I've flipped the first part of the test case I added for stability back
on in this commit. I'm taking it gradually to try and make sure the
build bots are happy this time.
llvm-svn: 233249
This fixes my stress tests non-determinism so far. However, I've not
started playing with templates, friends, or terrible macros. I've found
at least two more seeming instabilities and am just waiting for a test
case to actually trigger them.
llvm-svn: 233162
prune it when we have disabled implicit module generation and thus are
not using any cached modules.
Also update a test of explicitly generated modules to pass this CC1 flag
correctly.
This fixes an issue where Clang was dropping files into the source tree
while running its tests.
llvm-svn: 233117
There are two aspects of non-determinism fixed here, which was the
minimum required to cause at least an empty module to be deterministic.
First, the random number signature is only inserted into the module when
we are building modules implicitly. The use case for these random
signatures is to work around the very fact that modules are not
deterministic in their output when working with the implicitly built and
populated module cache. Eventually this should go away entirely when
we're confident that Clang is producing deterministic output.
Second, the on-disk hash table is populated based on the order of
iteration over a DenseMap. Instead, use a MapVector so that we can walk
it in insertion order.
I've added a test that an empty module, when built twice, produces the
same binary PCM file.
llvm-svn: 233115
for a DeclContext, and fix propagation of exception specifications along
redeclaration chains.
This reverts r232905, r232907, and r232907, which reverted r232793, r232853,
and r232853.
One additional change is present here to resolve issues with LLDB: distinguish
between whether lexical decls missing from the lookup table are local or are
provided by the external AST source, and still look in the external source if
that's where they came from.
llvm-svn: 232928
give an exception specification to a declaration that didn't have an exception
specification in any of our imported modules, emit an update record ourselves.
Without this, code importing the current module would not see an exception
specification that we could see and might have relied on.
llvm-svn: 232870
When we need to build the lookup table for a DeclContext, we used to pull in
all lexical declarations for the context; instead, just build a lookup table
for the local lexical declarations. We previously didn't guarantee that the
imported declarations would be in the returned map, but in some cases we'd
happen to put them all in there regardless. Now we're even lazier about this.
This unnecessary work was papering over some other bugs:
- LookupVisibleDecls would use the DC for name lookups in the TU in C, and
this was not guaranteed to find all imported names (generally, the DC for
the TU in C is not a reliable place to perform lookups). We now use an
identifier-based lookup mechanism for this.
- We didn't actually load in the list of eagerly-deserialized declarations
when importing a module (so external definitions in a module wouldn't be
emitted by users of those modules unless they happened to be deserialized
by the user of the module).
llvm-svn: 232793
consumers of that module.
Previously, such a file would only be available if the module happened to
actually import something from that module.
llvm-svn: 232583
namespace to not merge properly.
We have an invariant here: after a declaration reads its canonical declaration,
it can assume the canonical declaration is fully merged. This invariant can be
violated if deserializing some declaration triggers the deserialization of a
later declaration, because that later declaration can in turn deserialize a
redeclaration of that first declaration before it is fully merged.
The anonymous namespace for a namespace gets stored with the first declaration
of that namespace, which may be before its parent namespace, so defer loading
it until after we've finished merging the surrounding namespace.
llvm-svn: 232455
building its redecl chains, make sure we pull in the redeclarations of those
canonical declarations.
It's pretty difficult to reach a situation where we can find more canonical
declarations of an entity while building its redecl chains; I think the
provided testcase (4 modules and 7 declarations) cannot be reduced further.
llvm-svn: 232411
with a subset of the existing target CPU features or mismatched CPU
names.
While we can't check that the CPU name used to build the module will end
up being able to codegen correctly for the translation unit, we actually
check that the imported features are a subset of the existing features.
While here, rewrite the code to use std::set_difference and have it
diagnose all of the differences found.
Test case added which walks the set relationships and ensures we
diagnose all the right cases and accept the others.
No functional change for implicit modules here, just better diagnostics.
llvm-svn: 232248
headers even if they arrived when merging non-system modules.
The idea of this code is that we don't want to warn the user about
macros defined multiple times by their system headers with slightly
different definitions. We should have this behavior if either the
macro comes from a system module, or the definition within the module
comes from a system header. Previously, we would warn on ambiguous
macros being merged when they came from a users modules even though they
only showed up via system headers.
By surviving this we can handle common system header macro differences
like differing 'const' qualification of pointers due to some headers
predating 'const' being valid in C code, even when those systems headers
are pre-built into a system module.
Differential Revision: http://reviews.llvm.org/D8310
llvm-svn: 232149
definition, be sure to update the definition data on all declarations, not just
the canonical one, since the pattern might not be in the list of pending
definitions (if it used to be canonical itself).
One-line fix by me; reduced testcase by Daniel Jasper!
llvm-svn: 231950
specification, update all prior declarations if the new one has an explicit
exception specification and the prior ones don't.
Patch by Vassil Vassilev! Some minor tweaking and test case by me.
llvm-svn: 231738
move the operator delete updating into a separate update record so we can cope
with updating another module's destructor's operator delete.
llvm-svn: 231735
check that private headers are in a list matching the role. (We can't perform
the opposite checks for non-private headers because we infer those.)
llvm-svn: 231728
We used to save out and eagerly load a (potentially huge) table of merged
formerly-canonical declarations when we loaded each module. This was extremely
inefficient in the presence of large amounts of merging, and didn't actually
save any merging lookup work, because we still needed to perform name lookup to
check that our merged declaration lists were complete. This also resulted in a
loss of laziness -- even if we only needed an early declaration of an entity, we
would eagerly pull in all declarations that had been merged into it regardless.
We now store the relevant fragments of the table within the declarations
themselves. In detail:
* The first declaration of each entity within a module stores a list of first
declarations from imported modules that are merged into it.
* Loading that declaration pre-loads those other entities, so that they appear
earlier within the redeclaration chain.
* The name lookup tables list the most recent local lookup result, if there
is one, or all directly-imported lookup results if not.
llvm-svn: 231424
Modules and Tooling tests in particular tend to want to change the cwd,
so we were missing test coverage in this area on Windows. It should now
be easier to write such portable tests.
llvm-svn: 231029
Richard Smith