Can not use C99 function names as variable names in C89

[llvmbot]

Bugzilla Link	15150
Version	unspecified
OS	All
Reporter	LLVM Bugzilla Contributor
CC	@gribozavr

Extended Description

The following code doesn't compile in clang, but does in gcc:

int logf = 5;
int main() {
        return logf;
}

# gcc test.c -o test -std=c89
# ./test; echo $?
5
# clang test.c -o test -std=c89
test.c:1:5: error: redefinition of 'logf' as different kind of symbol
int logf = 5;
    ^
test.c:1:5: note: previous definition is here
test.c:4:16: warning: incompatible pointer to integer conversion returning 'float (float)' from a function with result type 'int' [-Wint-conversion]
        return logf;
               ^~~~
1 warning and 1 error generated.

[llvmbot]

@llvm/issue-subscribers-c

[llvmbot]

@llvm/issue-subscribers-clang-frontend

[llvmbot]

Hi!

This issue may be a good introductory issue for people new to working on LLVM. If you would like to work on this issue, your first steps are:

1. Check that no other contributor has already been assigned to this issue. If you believe that no one is actually working on it despite an assignment, ping the person. After one week without a response, the assignee may be changed.
2. In the comments of this issue, request for it to be assigned to you, or just create a pull request after following the steps below. Mention this issue in the description of the pull request.
3. Fix the issue locally.
4. Run the test suite locally. Remember that the subdirectories under test/ create fine-grained testing targets, so you can e.g. use make check-clang-ast to only run Clang's AST tests.
5. Create a Git commit.
6. Run git clang-format HEAD~1 to format your changes.
7. Open a pull request to the upstream repository on GitHub. Detailed instructions can be found in GitHub's documentation. Mention this issue in the description of the pull request.

If you have any further questions about this issue, don't hesitate to ask via a comment in the thread below.

[llvmbot]

@llvm/issue-subscribers-good-first-issue

Author: None (llvmbot)

| | | | --- | --- | | Bugzilla Link | [15150](https://llvm.org/bz15150) | | Version | unspecified | | OS | All | | Reporter | LLVM Bugzilla Contributor | | CC | @gribozavr |

Extended Description

The following code doesn't compile in clang, but does in gcc:

int logf = 5;
int main() {
return logf;
}

gcc test.c -o test -std=c89

./test; echo $?

5

clang test.c -o test -std=c89

test.c:1:5: error: redefinition of 'logf' as different kind of symbol
int logf = 5;
^
test.c:1:5: note: previous definition is here
test.c:4:16: warning: incompatible pointer to integer conversion returning 'float (float)' from a function with result type 'int' [-Wint-conversion]
return logf;
^~~~
1 warning and 1 error generated.

[tlemy]

I am working on this

[vinay-deshmukh]

@tlemy are you still working on this one?

[tlemy]

@vinay-deshmukh no

[vinay-deshmukh]

Thanks, I'll take this up then!