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User-Agent: Mozilla/5.0 Galeon/1.2.10 (X11; Linux i686; U;) Gecko/20030314

Description of problem:
Following C source compiles cleanly with gcc -c -W -Wno-system-headers -O

#include <math.h>
int main(int argc, char *argv[])
{
  if (!argc) return 1;
  else return 0;
}

If one however changes the `return 1' to just `return', and thus creating a
function that can return either with or without a value

#include <math.h>
int main(int argc, char *argv[])
{
  if (!argc) return;
  else return 0;
}

gcc notices it not only in this source, but in math.h too, giving a few dozens
of warnings starting with

/usr/include/bits/mathinline.h: In function `__sgn':
/usr/include/bits/mathinline.h:291: warning: this function may return with or
without a value
/usr/include/bits/mathinline.h: In function `__sgnf':
/usr/include/bits/mathinline.h:291: warning: this function may return with or
without a value
...


Version-Release number of selected component (if applicable):
gcc-3.2.2-5

How reproducible:
Always

Steps to Reproduce:
1. create file z.c, as described in the second example above
2. compile it gcc -c -W -Wno-system-headers -O z.c
3. for comparison, do the same with the first example above
    

Actual Results:  Described above.

Expected Results:  Only a single warning:

z.c: In function `main':
z.c:7: warning: this function may return with or without a value


Additional info: