[Bug c/40097] New: inconsistent printf handling

[Andrey dot Martchovsky at gmail dot com]

The following code results in a segmentation fault at Line 7.

1:#include <stdio.h>
2:int main(){
3:      const char *tmp = NULL;
4:      printf("%s \n",NULL);
5:      printf("%s\n",NULL);
6:      printf("%s \n",tmp);
7:      printf("%s\n",tmp);
8:      return 1;
9:}

I've traced the bug to the code optimization in

/usr/src/gcc-4.3/gcc-4.3.3/gcc/builtins.c
fold_builtin_printf()

the printf() is replaced with puts(), which has no null handling

The alternate solution would be to add a NULL check to puts() or putc() in
libc.

This inconsistency is a major setback when porting code from Windows to Linux
as MCVC++ compiles the above code correctly and GCC does not.


-- 
           Summary: inconsistent printf handling
           Product: gcc
           Version: 4.3.3
            Status: UNCONFIRMED
          Severity: blocker
          Priority: P3
         Component: c
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: Andrey dot Martchovsky at gmail dot com
GCC target triplet: gcc (Ubuntu 4.3.3-5ubuntu4) 4.3.3


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40097