gcc: explicitely enable C99 and 'long long' support

base/gcc/gcc.conf

@@ -118,6 +118,10 @@ fi
 # only C and C++ by default, and on every stage
 languages="c,c++"
 
+# explicitely enable C99 and 'long long' support
+var_append confopt ' ' "--enable-c99"
+var_append confopt ' ' "--enable-long-long"
+
 # build prerequisites
 var_append extraconfopt ' ' "--with-gmp=$( pkgprefix -r gmp )"
 var_append extraconfopt ' ' "--with-gmp-lib=$( pkgprefix -r libdir gmp )"