hasName AST matcher is confused by extern "C" in namespace

[Boddlnagg]

Bugzilla Link	42193
Resolution	FIXED
Resolved on	Feb 27, 2020 04:13
Version	unspecified
OS	Windows NT
Blocks	#43900
CC	@zmodem,@zygoloid
Fixed by commit(s)	rG16cabf278fc8c14d415e677ce0bc40d46a6de30d

Extended Description

Given the following code:

namespace foo {
extern "C" void test() {}
}

... I expect an AST matcher declared as functionDecl(hasName("::foo::test")) to match the function, but functionDecl(hasName("::test")) should not match. However, the opposite is the case. (see the example on Compiler Explorer: http://ce.steveire.com/z/VDTi_g)

When I do this locally with a build with assertions, I get an assertion failure at

llvm-project/clang/lib/ASTMatchers/ASTMatchersInternal.cpp

Line 540 in bca56ab

assert(matchesNodeFullFast(Node) == matchesNodeFullSlow(Node));

, so I think the problem is that matchesNodeFullFast does not correctly handle extern "C" functions.

[llvmbot]

Got a patch in the work https://reviews.llvm.org/D75202. Added bonus it doesn't fire off those assertions too.

[llvmbot]

Fixed in https://reviews.llvm.org/rG16cabf278fc8c14d415e677ce0bc40d46a6de30d

As this causes a crash I'll mark it as a release blocker, probably wont make it in time though

[zmodem]

Fixed in https://reviews.llvm.org/rG16cabf278fc8c14d415e677ce0bc40d46a6de30d

As this causes a crash I'll mark it as a release blocker, probably wont make
it in time though

It looks like a very safe change though. Pushed to 10.x as 8f2858e.

[Boddlnagg]

mentioned in issue llvm/llvm-bugzilla-archive#43639

[zmodem]

mentioned in issue #43900