[Bug c/27413] New: compiling with -ansi puts in broken version of atanh

["anonymous at mailinator dot com" <gcc-bugzilla@gcc.gnu.org>]

If you use -ansi to compile a program that uses the atanh function, the
compiler somehow replaces atanh with a function that just returns 0.  I think
the compiler should either put in the correct atanh function or refuses to
link/compile.  The following shows how to reproduce the bug:


$ cat > bug.c

#include <math.h>
#include <stdio.h>
#include <stdlib.h>

int main() { printf("atanh(%f) returns %f!\n",.32,atanh(.32)); return 0;}

$ gcc bug.c -o bug.exe -lm && bug.exe
atanh(0.320000) returns 0.331647!
$ gcc -ansi bug.c -o bug.exe -lm && bug.exe
atanh(0.320000) returns 0.000000!


-- 
           Summary: compiling with -ansi puts in broken version of atanh
           Product: gcc
           Version: 3.3.2
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: anonymous at mailinator dot com


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=27413