From: buers AT gmx DOT de (Dieter Buerssner)
Newsgroups: comp.os.msdos.djgpp
Subject: Gdb and floating point
Date: 25 Mar 2000 15:01:41 GMT
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To: djgpp AT delorie DOT com
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Reply-To: djgpp AT delorie DOT com

Is there a possibility to print floating point values, that are 
currently in a floating point register, by the name of the variable?
(info all-register shows the values, but it can be very tedious
to find out which register corresponds to which name.)

To give an example, I compiled the following program:

#include <stdio.h>

double one = 1.0;

int main(void)
{
  double d;

  d = 2.0*one;
  printf("%f\n", d);
  return 0;
}

with gcc -g -O test.c (or -gstabs+ instead of -g).
When I set a breakpoint to the printf line and type

"p d"

after the breakpoint is hit, gdb (4.18) replies with

$1 = 1.4128210791984452e-303

which is obviously wrong. ("p one" works as expected)

-- Dieter