From: Matthew Fernandez <matthew.fernandez@gmail.com>
Date: Wed, 12 Oct 2022 04:02:18 +0000 (-0700)
Subject: remove suppression of -ffast-math when building with ICC
X-Git-Tag: 7.0.0~14^2~2
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=b1339c1c8e4570c18f859eb13c454d26ea6b56c6;p=graphviz

remove suppression of -ffast-math when building with ICC

The Intel C Compiler does not support the `-ffast-math` command line option, so
this logic was suppressing it. But it is coming before anything in the Graphviz
build system itself that would add `-ffast-math`. So it is actually suppressing
a `-ffast-math` addition coming from the user’s environment. If you are a user
compiling Graphviz with ICC, I have a very simple alternative for you: do not
pass `-ffast-math` explicitly.

Gitlab: #1412, #2296
---

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 8747caf57..2a8265b46 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -14,6 +14,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
   struct.
 - When using the CMake build system, the minimum requirement has been increased
   from CMake 3.9 to CMake 3.10.2.
+- When compiling Graphviz with the Intel C Compiler, the Autotools build system
+  no longer suppresses `-ffast-math`. Users relying on this are encouraged to
+  investigate what in their build environment is appending a flag their C
+  compiler does not support.
 
 ### Removed
 
diff --git a/configure.ac b/configure.ac
index 90212ad9f..49dd28cef 100644
--- a/configure.ac
+++ b/configure.ac
@@ -382,8 +382,6 @@ else
 	    CFLAGS="${CFLAGS} -wd269"
 	    # icc doesn't like -pipe
 	    CFLAGS=`echo ${CFLAGS} | sed 's/ -pipe//'`
-	    # icc doesn't like -ffast-math
-	    CFLAGS=`echo ${CFLAGS} | sed 's/ -ffast-math//'`
 	    ;;
 	* )
 	    case "${build}" in