Re: pkg/36356

[Raymond Meyer <raymond.meyer%rambler.ru@localhost>]

The following reply was made to PR pkg/36356; it has been noted by GNATS.

From: Raymond Meyer <raymond.meyer%rambler.ru@localhost>
To: <gnats-bugs%NetBSD.org@localhost>
Cc: <mark%mcs.vuw.ac.nz@localhost>
Subject: Re: pkg/36356
Date: Sun, 10 Jun 2007 16:15:02 +0400

 Mark, the patch that you incorporated into 3.5.7 is not entirely 
 correct. The problem on Solaris is isinf() and friends are declared as 
 macros via math.h header. If you compile with gcc and -std=c99 flag then 
 the macros are included, without the flag the macros are not included 
 and compilation fails. If you run g++ then the comiler does not seem to 
 pick up those macros no matter what you do, so C++ programs fail to 
 compile in all cases. Some gcc compilers assume -std=c99 by default, in 
 which case tests for isinf() succeed and later C++ code that has calls 
 to isinf() fails to compile.
 
 I think the correct patch would be to test if isnan() and isinf() are 
 functions or macros. A way to do it is to declare a pointer to function 
 isnan() or isinf(), this will fail to compile if they are macros:
 
 diff -u configure.orig configure
 --- configure.orig      Sun Jun 10 13:05:55 2007
 +++ configure   Sun Jun 10 13:08:44 2007
 @@ -56721,10 +56721,11 @@
  /* end confdefs.h.  */
  #include <math.h>
  float f;
 +int (*isnan_ptr)(float) = &isnan;
  int
  main ()
  {
 -return isnan(f)
 +return isnan_ptr(f)
    ;
    return 0;
  }
 @@ -56796,10 +56797,11 @@
  /* end confdefs.h.  */
  #include <math.h>
  float f;
 +int (*isinf_ptr)(float) = &isinf;
  int
  main ()
  {
 -return isinf(f)
 +return isinf_ptr(f)
    ;
    return 0;
  }