The idiom:
```
DeclContext::lookup_result R = DeclContext::lookup(Name);
for (auto *D : R) {...}
```
is not safe when in the loop body we trigger deserialization from an AST file.
The deserialization can insert new declarations in the StoredDeclsList whose
underlying type is a vector. When the vector decides to reallocate its storage
the pointer we hold becomes invalid.
This patch replaces a SmallVector with an singly-linked list. The current
approach stores a SmallVector<NamedDecl*, 4> which is around 8 pointers.
The linked list is 3, 5, or 7. We do better in terms of memory usage for small
cases (and worse in terms of locality -- the linked list entries won't be near
each other, but will be near their corresponding declarations, and we were going
to fetch those memory pages anyway). For larger cases: the vector uses a
doubling strategy for reallocation, so will generally be between half-full and
full. Let's say it's 75% full on average, so there's N * 4/3 + 4 pointers' worth
of space allocated currently and will be 2N pointers with the linked list. So we
break even when there are N=6 entries and slightly lose in terms of memory usage
after that. We suspect that's still a win on average.
Thanks to @rsmith!
Differential revision: https://reviews.llvm.org/D91524
Currently TypePrinter lumps anonymous classes and unnamed classes in one group "anonymous" this is not correct and can be confusing in some contexts.
Differential Revision: https://reviews.llvm.org/D96807
Currently TypePrinter lumps anonymous classes and unnamed classes in one group "anonymous" this is not correct and can be confusing in some contexts.
Differential Revision: https://reviews.llvm.org/D96807
The check only runs in debug mode during serialization, but
assert()-fail on:
struct S { const int& x = 7; };
in C++ mode.
Differential Revision: https://reviews.llvm.org/D94804
For a default visibility external linkage definition, dso_local is set for ELF
-fno-pic/-fpie and COFF and Mach-O. Since default clang -cc1 for ELF is similar
to -fpic ("PIC Level" is not set), this nuance causes unneeded binary format differences.
To make emitted IR similar, ELF -cc1 -fpic will default to -fno-semantic-interposition,
which sets dso_local for default visibility external linkage definitions.
To make this flip smooth and enable future (dso_local as definition default),
this patch replaces (function) `define ` with `define{{.*}} `,
(variable/constant/alias) `= ` with `={{.*}} `, or inserts appropriate `{{.*}} `.
For a definition (of most linkage types), dso_local is set for ELF -fno-pic/-fpie
and COFF, but not for Mach-O. This nuance causes unneeded binary format differences.
This patch replaces (function) `define ` with `define{{.*}} `,
(variable/constant/alias) `= ` with `={{.*}} `, or inserts appropriate `{{.*}} `
if there is an explicit linkage.
* Clang will set dso_local for Mach-O, which is currently implied by TargetMachine.cpp. This will make COFF/Mach-O and executable ELF similar.
* Eventually I hope we can make dso_local the textual LLVM IR default (write explicit "dso_preemptable" when applicable) and -fpic ELF will be similar to everything else. This patch helps move toward that goal.
This attribute permits a typedef to be associated with a class template
specialization as a preferred way of naming that class template
specialization. This permits us to specify that (for example) the
preferred way to express 'std::basic_string<char>' is as 'std::string'.
The attribute is applied to the various class templates in libc++ that have
corresponding well-known typedef names.
This is a re-commit. The previous commit was reverted because it exposed
a pre-existing bug that has since been fixed / worked around; see
PR48434.
Differential Revision: https://reviews.llvm.org/D91311
Ensure that we can deserialize a TypedefType even while in the middle of
deserializing its TypedefDecl, by removing the need to look at the
TypedefDecl while constructing the TypedefType.
This fixes all the currently-known failures for PR48434, but it's not a
complete fix, because we can still trigger deserialization cycles, which
are not supposed to happen.
This change exposed a pre-existing issue with deserialization cycles
caused by a combination of attributes and template instantiations
violating the deserialization ordering restrictions; see PR48434 for
details.
A previous commit attempted to work around PR48434, but appears to have
only been a partial fix, and fixing this properly seems non-trivial.
Backing out for now to unblock things.
This reverts commit 98f76adf4e and
commit a64c26a47a.
This is really just a workaround for a more fundamental issue in the way
we deserialize attributes. See PR48434 for details.
Also fix tablegen code generator to produce more correct indentation to
resolve buildbot issues with -Werror=misleading-indentation firing
inside the generated code.
non-type template parameters.
Create a unique TemplateParamObjectDecl instance for each such value,
representing the globally unique template parameter object to which the
template parameter refers.
No IR generation support yet; that will follow in a separate patch.
This fixes miscomputation of __builtin_constant_evaluated in the
initializer of a variable that's not usable in constant expressions, but
is readable when constant-folding.
If evaluation of a constant initializer fails, we throw away the
evaluated result instead of keeping it as a non-constant-initializer
value for the variable, because it might not be a correct value.
To avoid regressions for initializers that are foldable but not formally
constant initializers, we now try constant-evaluating some globals in
C++ twice: once to check for a constant initializer (in an mode where
is_constannt_evaluated returns true) and again to determine the runtime
value if the initializer is not a constant initializer.
Old GCC used to aggressively fold VLAs to constant-bound arrays at block
scope in GNU mode. That's non-conforming, and more modern versions of
GCC only do this at file scope. Update Clang to do the same.
Also promote the warning for this from off-by-default to on-by-default
in all cases; more recent versions of GCC likewise warn on this by
default.
This is still slightly more permissive than GCC, as pointed out in
PR44406, as we still fold VLAs to constant arrays in structs, but that
seems justifiable given that we don't support VLA-in-struct (and don't
intend to ever support it), but GCC does.
Differential Revision: https://reviews.llvm.org/D89523
When parsing a C++17 binding declaration, we first create the
BindingDecls in Sema::ActOnDecompositionDeclarator, and then build the
DecompositionDecl in Sema::ActOnVariableDeclarator, so the contained
BindingDecls are never null. But when deserializing, we read the
DecompositionDecl with all properties before filling in the Bindings.
Among other things, reading a declaration reads whether it's invalid,
then calling setInvalidDecl which assumes that all bindings of the
DecompositionDecl are available, but that isn't the case.
Deserialization should just set all properties directly without invoking
subsequent functions, so we just set the flag without using the setter.
Fixes PR34960.
Reviewed By: rsmith
Differential Revision: https://reviews.llvm.org/D86207
This fixes a crash when declaring a destructor with a wrong name, then
writing result to pch file and loading it again. The PCH storage uses
DeclarationNameKey as key and it is the same key for both the invalid
destructor and the implicit one that was created because the other one
was invalid. When querying for the Foo::~Foo we end up getting
Foo::~Bar, which is then rejected and we end up with nullptr in
CXXRecordDecl::GetDestructor().
Fixes https://bugs.llvm.org/show_bug.cgi?id=47270
Differential Revision: https://reviews.llvm.org/D86624
This addresses a FIXME in ASTReader.
Modules were already re-exported for Preprocessor, but not for Sema.
The result was that, with -fmodules-local-submodule-visibility, all AST
nodes belonging to a module that was loaded in a premable where not
accesible from the main part of the file and a diagnostic recommending
importing those modules would be generated.
Differential Revision: https://reviews.llvm.org/D86069
There are three fields that the FPOptions default constructor sets to
non-zero values; those fields previously could have been zero or
non-zero depending on whether they'd been explicitly removed from the
FPOptionsOverride set. However, that doesn't seem to ever actually
happen, so this is NFC, except that it makes the AST file representation
of FPOptionsOverride make more sense.
We don't appear to use these FPOptions for anything right now, but
they shouldn't be uninitialized because that makes our AST file output
nondeterministic.
`TemplateTypeParmDecl::hasTypeConstraint` is not a safe guard for
checking `TemplateTypeParmDecl::getTypeConstraint()` result is null.
in somecases (e.g. implicit deduction guide templates synthesized from the
constructor, immediately-declared constraint is not formed because of an error),
hasTypeConstraint returns false, and getTypeConstraint returns a nullptr.
Fix https://bugs.llvm.org/show_bug.cgi?id=46790
Differential Revision: https://reviews.llvm.org/D84455
This way should be the same like with a.pcm for modules.
An alternative way is 'clang++ -c empty.cpp -include-pch a.pch -o a.o
-Xclang -building-pch-with-obj', which is what clang-cl's /Yc does
internally.
Differential Revision: https://reviews.llvm.org/D83716
Allow to build PCH's (with -building-pch-with-obj and the extra .o file)
with -fmodules-codegen -fmodules-debuginfo to allow emitting shared code
into the extra .o file, similarly to how it works with modules. A bit of
a misnomer, but the underlying functionality is the same. This saves up
to 20% of build time here. The patch is fairly simple, it basically just
duplicates -fmodules checks to also alternatively check
-building-pch-with-obj.
This already got committed as cbc9d22e49,
but then got reverted in 7ea9a6e022
because of PR44953, as discussed in D74846. This is a corrected version
which does not include two places for the PCH case that aren't included
in the modules -fmodules-codegen path either.
Differential Revision: https://reviews.llvm.org/D69778
Summary:
Patch adds tests for mangling of svbfloat16_t and several other type
related tests.
Reviewers: sdesmalen, kmclaughlin, fpetrogalli, efriedma
Reviewed By: sdesmalen, fpetrogalli
Differential Revision: https://reviews.llvm.org/D82668
This reverts commit defd43a5b3.
with correction to solve msan report
To solve https://bugs.llvm.org/show_bug.cgi?id=46166 where the
floating point settings in PCH files aren't compatible, rewrite
FPFeatures to use a delta in the settings rather than absolute settings.
With this patch, these floating point options can be benign.
Reviewers: rjmccall
Differential Revision: https://reviews.llvm.org/D81869
This reverts commit b55d723ed6.
Reapply Modify FPFeatures to use delta not absolute settings
To solve https://bugs.llvm.org/show_bug.cgi?id=46166 where the
floating point settings in PCH files aren't compatible, rewrite
FPFeatures to use a delta in the settings rather than absolute settings.
With this patch, these floating point options can be benign.
Reviewers: rjmccall
Differential Revision: https://reviews.llvm.org/D81869
templated class.
When a defaulted operator<=> results in the injection of a defaulted
operator==, that operator== can be named by unqualified name within the
same class, even if the class is templated. To make this work, perform
the transform from defaulted operator<=> to defaulted operator== in the
template definition context instead of the template instantiation
context.
This results in our substituting into a declaration from a context where
we don't have a full list of template arguments (or indeed any), for
which we are now more careful to not spuriously instantiate declarations
that are not dependent on the arguments we're substituting.
Add -fpch-instantiate-templates which makes template instantiations be
performed already in the PCH instead of it being done in every single
file that uses the PCH (but every single file will still do it as well
in order to handle its own instantiations). I can see 20-30% build
time saved with the few tests I've tried.
The change may reorder compiler output and also generated code, but
should be generally safe and produce functionally identical code.
There are some rare cases that do not compile with it,
such as test/PCH/pch-instantiate-templates-forward-decl.cpp. If
template instantiation bailed out instead of reporting the error,
these instantiations could even be postponed, which would make them
work.
Enable this by default for clang-cl. MSVC creates PCHs by compiling
them using an empty .cpp file, which means templates are instantiated
while building the PCH and so the .h needs to be self-contained,
making test/PCH/pch-instantiate-templates-forward-decl.cpp to fail
with MSVC anyway. So the option being enabled for clang-cl matches this.
Differential Revision: https://reviews.llvm.org/D69585
templated class.
When a defaulted operator<=> results in the injection of a defaulted
operator==, that operator== can be named by unqualified name within the
same class, even if the class is templated. To make this work, perform
the transform from defaulted operator<=> to defaulted operator== in the
template definition context instead of the template instantiation
context.
This results in our substituting into a declaration from a context where
we don't have a full list of template arguments (or indeed any), for
which we are now more careful to not spuriously instantiate declarations
that are not dependent on the arguments we're substituting.
Summary:
DelayedTemplateParsing is marked as BENIGN_LANGOPT, so we are allowed to
use a delayed template in a non-delayed TU.
(This is clangd's default configuration on windows: delayed-template-parsing
is on for the preamble and forced off for the current file)
However today clang fails to parse implicit instantiations in a non-dtp
TU of templates defined in a dtp PCH file (and presumably module?).
In this case the delayed parser is not registered, so the function is
simply marked "delayed" again. We then hit an assert:
end of TU template instantiation should not create more late-parsed templates
Reviewers: rsmith
Subscribers: ilya-biryukov, usaxena95, cfe-commits, kadircet
Tags: #clang
Differential Revision: https://reviews.llvm.org/D81474
eee944e7f adds the new BuiltinBitCastExpr, but does not set the Code member of
ASTStmtWriter. This is not correct and causes an assertion failue in
ASTStmtWriter::emit() when building PCHs that contain __builtin_bit_cast. This
commit adds serialization::EXPR_BUILTIN_BIT_CAST and handles
ASTStmtWriter::Code properly.
Differential revision: https://reviews.llvm.org/D80360
This bit was assumed to be always false for ParmVarDecls, but attribute
objc_externally_retained now can produce it.
Differential revision: https://reviews.llvm.org/D74417
Summary:
omp.h header file defines omp_null_allocator as a predefined allocator,
need to consider it also as a predefined allocator.
Reviewers: jdoerfert
Subscribers: jholewinski, yaxunl, guansong, cfe-commits, caomhin
Tags: #clang
Differential Revision: https://reviews.llvm.org/D79186
test cases
Add support for #pragma float_control
Reviewers: rjmccall, erichkeane, sepavloff
Differential Revision: https://reviews.llvm.org/D72841
This reverts commit 85dc033cac, and makes
corrections to the test cases that failed on buildbots.
If a PCH is used for compilation, SourceManager::isInMainFile()
returns true even for the "<built-in>" predefines area. Using -D
only for the TU compilation may trigger -Wunused-macros for it.
It is admitedly a bit fishy to set a macro only for a TU and not
for the PCH, but this works fine if the PCH does not use the macro
(I couldn't find a statement on this for Clang, but GCC explicitly
allows this in the docs).
Differential Revision: https://reviews.llvm.org/D73846