To: WKIM AT vms DOT cis DOT pitt DOT edu, djgpp AT sun DOT soe DOT clarkson DOT EDU
From: "Peter E. Miller"  <PMILLER AT dpc2 DOT hdos DOT hac DOT com>
Date:         7 May 93 09:15:40 ET
Subject:      Re: gcc hangs: again
Reply-To: miller AT hac2arpa DOT hac DOT com

Wonkoo Kim writes:

> I posted a problem that gcc is stucked when compiling a certain program.
> In verifying the program, I found a new fact.  My file contains several
> functions and a function has several return() statements at the end of the
> function, ...
>   ...
> When I changed this conditional branches into if/else if/else way, then gcc
> did hang.  I.e.
>   ...
> didn't hang the gcc.

I took both pieces of code and made the two source files at the end
of this note. I used
  gcc -Wall -S test#.c
on both. During compilation of test1.c a spurious character
appeared at the top of my screen. Compilation of test2.c doesn't do
this.

When I used
  gcc -Wall -O -S test#.c
a spurious character appeared on my screen during compilation of both,
at the same location. These tests are repeatable for me.

I have been using DJGPP 1.09 (2.2.2) ever since it was released and
never noticed a problem like this. I've used it on a 386-16 ISA and a
486-50 EISA without problems.

---- test1.c --------------------------------------------------------
#include <float.h>
#include <math.h>

double
test (double x, double y)
{
  if (y == 0.) return (23.6);
  if (x == 0.) return (DBL_MAX);
  return (10.*log10(y / x));
}
---- test2.c --------------------------------------------------------
#include <float.h>
#include <math.h>

double
test (double x, double y)
{
  double p;

  if (y == 0.)
    p = 23.6;
  else if (x == 0.)
    p = DBL_MAX;
  else
    p = 10.*log10(y/x);
  return(p);
}
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