c11: Accepts ill-formed program with inline function definition containing modifiable variable with static storage duration.

[yeah-boi]

Bugzilla Link	40177
Version	trunk
OS	All
CC	@hfinkel,@zygoloid

Extended Description

Test case (prog.c):

inline void f()
{
static int x;
}

int main()
{
}

Compilation command line:

clang prog.c -Wall -Wextra -std=c11 -pedantic-errors

Observed behaviour:

No error message outputed. Only a warning message outputed.

Expected behaviour:

An error message outputed.

The program violates 6.7.4/3:

"An inline definition of a function with external linkage shall not contain
 a definition of a modifiable object with static or thread storage duration,
 and shall not contain a reference to an identifier with internal linkage."

Since -pedantic-errors is used we should get an error instead of a warning.

Note:

GCC gives the expected error message.

[AaronBallman]

The warning is correct but insufficient for -pedantic-errors.

This may be possible to resolve by changing def warn_static_local_in_extern_inline : Warning< to use ExtWarn instead, but I've not checked to see what fallout comes from such a change.

[llvmbot]

@llvm/issue-subscribers-c

[llvmbot]

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[Susikrishna]

I would like to work on this issue