From 9168e2470d5203661faa5500361b7eb493aa24dd Mon Sep 17 00:00:00 2001 From: Marcel Raad Date: Fri, 14 Apr 2017 12:48:27 +0200 Subject: curl-compilers.m4: turn implicit function declarations into errors This adds -Werror-implicit-function-declaration for GCC 2.95+ so that these errors are visible at the point where they occur instead of only at link time. Implicit function declarations are illegal in C99 and C++ anyway, and the same warning has been turned into an error for ICC in commit 3072c5b8a127057aa922b7c51051bbb4a630b091. Ref: https://gcc.gnu.org/onlinedocs/gcc-2.95.2/gcc_2.html#SEC8 Ref: https://curl.haxx.se/mail/lib-2017-04/0001.html Closes https://github.com/curl/curl/pull/1419 --- m4/curl-compilers.m4 | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/m4/curl-compilers.m4 b/m4/curl-compilers.m4 index 3219baf6b..19462582f 100644 --- a/m4/curl-compilers.m4 +++ b/m4/curl-compilers.m4 @@ -577,8 +577,11 @@ AC_DEFUN([CURL_SET_COMPILER_BASIC_OPTS], [ # GNU_C) # - dnl Placeholder - tmp_CFLAGS="$tmp_CFLAGS" + dnl turn implicit-function-declaration warning into error, + dnl at least gcc 2.95 and later support this + if test "$compiler_num" -ge "295"; then + tmp_CFLAGS="$tmp_CFLAGS -Werror-implicit-function-declaration" + fi ;; # HP_UX_C) -- cgit v1.2.3