Re: detection of gcc version

[Eric Blake]

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According to Vincent Torri on 1/10/2009 11:09 PM:
> 
> Hey,
> 
> I would like to detect the major version of gcc in configure.ac. A guy
> told me to use sed like that:
> 
> GCC_MAJOR_VERSION=`$CC -dumpversion | sed "s/\..*//"`
> 
> Is there a better way to do that with autoconf macros ?

What about using preprocessor macros and AC_COMPILE_IFELSE?  For example,

#if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 2)
 int dummy;
#else
 not gcc, or gcc is too old
#endif

But in general, version number checks tend to be counterproductive; the
autoconf philosophy favors feature checks over version number checks.

- --
Don't work too hard, make some time for fun as well!

Eric Blake             address@hidden
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