I made some investigation yesterday and here is the result: ``` Diff'ing gcc/libstdc++-v3/include/c_global/cstdlib from gcc-5-branch and gcc-6-branch gives the following result: (git diff gcc-5-branch gcc-6-branch -- libstdc++-v3/include/c_global/cstdlib) ``` @@ -69,7 +69,11 @@ namespace std #else -#include <stdlib.h> +// Need to ensure this finds the C library's <stdlib.h> not a libstdc++ +// wrapper that might already be installed later in the include search path. +#define _GLIBCXX_INCLUDE_NEXT_C_HEADERS +#include_next <stdlib.h> +#undef _GLIBCXX_INCLUDE_NEXT_C_HEADERS // Get rid of those macros defined in <stdlib.h> in lieu of real functions. #undef abort ``` Replacing #include_next with #include fixes the problem.
However, I am not exactly clear about whether it is these headers (cstdlib and cmath currently, there might be more) that are the problem. In my point of view, it is the inversion of C and C++ header paths that is the problem. ------------------ Best regards, lh_mouse 2016-05-02
