Description of Problem:

gcc -O2 produces incorrect biniaries.

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

   gcc version 2.96 20000731 (Red Hat Linux 7.1 2.96-87)

How Reproducible:

   Each and every time.

Steps to Reproduce:
1. Put the following program in a file, maybe called bug.c, as follows:
#include <stdio.h>
 
#define           round(a)        (int)(((a)<0.0)?(a)-.5:(a)+.5)
 
int   zoomxoff;
 
short
SHZOOMX(int x)
{
  x = round(0.7*((x)-zoomxoff));
  return (short) x;
}
 
int main() {
  zoomxoff = 0;
  printf ("SHZOOMX(%d) = %hd (should be 70)\n", 100, SHZOOMX(100));
  printf ("SHZOOMX(%d) = %hd (should be -70)\n", -100, SHZOOMX(-100));
  return 0;
}      
 
2.  Compile the program with:

    gcc -O2 -o bug bug.c    

3.  Execute the program with:

    ./bug

Actual Results:

   SHZOOMX(100) = 0 (should be 70)
   SHZOOMX(-100) = -70 (should be
-70)                                                                   

Expected Results:

   SHZOOMX(100) = 70 (should be 70)
   SHZOOMX(-100) = -70 (should be
-70)                                                                   


Additional Information:
	
This problem goes away if you compile with 'gcc -O2 -fno-sched-interblock'.  The
bug also occurs thru gcc-3.0.4 released Feb 20, 2002, but goes away in
gcc-3.1-prerelease dated April 01, 2002.

Please let me know if I can be of further assitance.

Best Regards,


--George