From: Marcel Raad <Marcel.Raad@teamviewer.com>
Date: Tue, 30 May 2017 08:07:47 +0000 (+0200)
Subject: curl-compilers.m4: enable -Wshift-sign-overflow for clang
X-Git-Tag: curl-7_54_1~66
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=314a7fa3ceb74f90cc7cce28bef7517ef874f64c;p=thirdparty%2Fcurl.git

curl-compilers.m4: enable -Wshift-sign-overflow for clang

clang 2.9+ supports -Wshift-sign-overflow, which warns about undefined
behavior on signed left shifts when shifting by too many places.

Ref: https://github.com/curl/curl/issues/1516
Closes https://github.com/curl/curl/pull/1517
---

diff --git a/m4/curl-compilers.m4 b/m4/curl-compilers.m4
index 5890324468..673f640979 100644
--- a/m4/curl-compilers.m4
+++ b/m4/curl-compilers.m4
@@ -881,6 +881,11 @@ AC_DEFUN([CURL_SET_COMPILER_WARNING_OPTS], [
           if test "$compiler_num" -ge "101"; then
             tmp_CFLAGS="$tmp_CFLAGS -Wunused"
           fi
+          #
+          dnl Only clang 2.9 or later
+          if test "$compiler_num" -ge "209"; then
+            tmp_CFLAGS="$tmp_CFLAGS -Wshift-sign-overflow"
+          fi
         fi
         ;;
         #