[Tinycc-devel] Fwd: Bug#322913: tcc: _Bool exists but doesn't comply with C99

[Romain Francoise]

Hi,

A Debian user reported this bug about C99 compliance in TCC.

-------------------- Start of forwarded message --------------------
From: Hrvoje Niksic <address@hidden>
Subject: Bug#322913: tcc: _Bool exists but doesn't comply with C99
To: Debian Bug Tracking System <address@hidden>
Date: Sat, 13 Aug 2005 16:02:18 +0200

Package: tcc
Version: 0.9.23-1
Severity: normal

Tcc doesn't correctly implement casts from floating point types to _Bool. 
According to C99, such casts must return true for all numbers except 0:

   When any scalar value is converted to _Bool, the result is 0 if the value
   compares equal to 0; otherwise, the result is 1.

This means that (_Bool) 0.1 must be 1; with tcc it's 0.  The following
trivial program can be used to test this:

#include <stdio.h>
int
main (void)
{
  printf ("%d\n", (_Bool) 0.1);
  return 0;
}

The program prints 1 under Gcc (and other C99-compliant compilers I tested
it with, such as Sun's cc) and 0 under Tcc.  I know that Tcc doesn't aim for
C99 conformance, but it's confusing that it implements the _Bool type which
comes from C99, but not the associated semantics.

-------------------- End of forwarded message --------------------

Thanks,

-- 
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 : :' :        Romain Francoise <address@hidden>
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