<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/63573>63573</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            clang report error when compile with -D_FORTIFY_SOURCE=2
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            new issue
      </td>
    </tr>

    <tr>
      <th>Assignees</th>
      <td>
      </td>
    </tr>

    <tr>
      <th>Reporter</th>
      <td>
          Gcourage
      </td>
    </tr>
</table>

<pre>
    testcase
```c
#include <stdio.h>

extern int printf(const char *format, ...);
int main() {
   printf("Hello World\n");
   return 0;
}
```

```bash
clang -O2 -D_FORTIFY_SOURCE=2 test_1.c
```

output:
```
extern int printf(const char *format, ...);
 ^
/usr/include/x86_64-linux-gnu/bits/stdio2.h:111:17: note: expanded from macro 'printf'
  __printf_chk (__USE_FORTIFY_LEVEL - 1, __VA_ARGS__)
 ^
/usr/include/features.h:398:31: note: expanded from macro '__USE_FORTIFY_LEVEL'
#  define __USE_FORTIFY_LEVEL 2
 ^
test_1.c:3:12: error: expected ')'
/usr/include/x86_64-linux-gnu/bits/stdio2.h:111:17: note: expanded from macro 'printf'
  __printf_chk (__USE_FORTIFY_LEVEL - 1, __VA_ARGS__)
                ^
/usr/include/features.h:398:31: note: expanded from macro '__USE_FORTIFY_LEVEL'
#  define __USE_FORTIFY_LEVEL 2
                              ^
test_1.c:3:12: note: to match this '('
/usr/include/x86_64-linux-gnu/bits/stdio2.h:111:16: note: expanded from macro 'printf'
  __printf_chk (__USE_FORTIFY_LEVEL - 1, __VA_ARGS__)
               ^
test_1.c:3:12: warning: a function declaration without a prototype is deprecated in all versions of C and is treated as a zero-parameter prototype in C2x, con
flicting with a previous declaration [-Wdeprecated-non-prototype]
extern int printf(const char *format, ...);
 ^
/usr/include/x86_64-linux-gnu/bits/stdio2.h:111:3: note: expanded from macro 'printf'
  __printf_chk (__USE_FORTIFY_LEVEL - 1, __VA_ARGS__)
```
clang version:
```
clang version 15.0.5
Target: x86_64-unknown-linux-gnu
Thread model: posix
Selected GCC installation: /usr/lib/gcc/x86_64-linux-gnu/10
Candidate multilib: .;@m64
Selected multilib: .;@m64

```


gcc 12.2 compile pass
</pre>
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