Hello autoconfers, In the section where manual describes AC_PROG_CXX
http://www.gnu.org/s/hello/manual/autoconf/C_002b_002b-Compiler.html#C_002b_002b-Compiler it claims that shell variable GXX is set to ‘yes’ if using GNU C++ compiler. This seems to be inaccurate because when I build with, e.g., Intel compiler I get GXX set to yes as well. Looking into the code of macro _AC_LANG_COMPILER_GNU that sets this variable it looks like it relies on whether PP macro __GNUC__ is defined or not. It turns out that this is not a good way to determine whether GCC is used because many compilers defined that macro: http://gcc.gnu.org/ml/gcc/2008-07/threads.html#00025 Obviously it would be good if CXX behaves as documented but before that can be fixed I think the manual perhaps should be updated. Thank you, Peter
