http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51785
--- Comment #3 from vries at gcc dot gnu.org 2012-01-11 13:00:37 UTC --- This attempt at 'a glibc version check and defining the std::gets prototype in libstdc++' (PR 51773 comment 11) unbreaks the libstdc++ build: ... Index: libstdc++-v3/include/c_std/cstdio =================================================================== --- libstdc++-v3/include/c_std/cstdio (revision 183073) +++ libstdc++-v3/include/c_std/cstdio (working copy) @@ -88,6 +88,12 @@ #undef vprintf #undef vsprintf +#if __GLIBC_PREREQ (2,15) +extern "C" { + extern char *gets (char *__s) __attribute__((deprecated)); +} +#endif + namespace std { using ::FILE; Index: libstdc++-v3/include/c_global/cstdio =================================================================== --- libstdc++-v3/include/c_global/cstdio (revision 183073) +++ libstdc++-v3/include/c_global/cstdio (working copy) @@ -89,6 +89,12 @@ #undef vprintf #undef vsprintf +#if __GLIBC_PREREQ (2,15) +extern "C" { + extern char *gets (char *__s) __attribute__((deprecated)); +} +#endif + namespace std { using ::FILE; ...