How to test for gnu extensions

[William A. Hoffman]

At 07:40 AM 2/10/2006, David Faure wrote:
>On Thursday 09 February 2006 21:54, William A. Hoffman wrote:
>> The name of the macro is 
>> check_c_source_compiles not CheckCSourceCompiles.
>
>BTW that's quite surprising/inconsistent.
>The documentation talks about CheckCSourceCompiles, not about check_c_source_compiles.

The documentation is actually correct:

$ ./bin/cmake --help-module CheckCSourceCompiles
cmake version 2.3-20060209
  CheckCSourceCompiles
       macro which checks if the source code compiles

       CHECK_C_SOURCE_COMPILES(SOURCE VAR)

         SOURCE   - source code to try to compile
         VAR - variable to store size if the type exists.



       The following variables may be set before calling this macro to modify
       the way the check is run:

         CMAKE_REQUIRED_FLAGS = string of compile command line flags
         CMAKE_REQUIRED_DEFINITIONS = list of macros to define (-DFOO=bar)
         CMAKE_REQUIRED_INCLUDES = list of include directories
         CMAKE_REQUIRED_LIBRARIES = list of libraries to link


The convention for files is upper case/ lower case to separate the words.
However, since we use all caps for macro names, that does not work as well,
and we use _ to separate.

-Bill