Force ffp-contract to off

Author: derickr

NEWS

@@ -13,6 +13,8 @@ PHP                                                                        NEWS
 - Core:
   . Fixed bug GH-13970 (Incorrect validation of #[Attribute] flags type for
     non-compile-time expressions). (ilutov)
+  . Fixed bug GH-14140 (Floating point bug in range operation on Apple Silicon
+    hardware). (Derick, Saki)
 
 - DOM:
   . Fix crashes when entity declaration is removed while still having entity

configure.ac

@@ -218,6 +218,9 @@ case $host_cpu in
     ;;
 esac
 
+dnl See https://github.com/php/php-src/issues/14140
+AX_CHECK_COMPILE_FLAG([-ffp-contract=off], [CFLAGS="$CFLAGS -ffp-contract=off"])
+
 dnl Mark symbols hidden by default if the compiler (for example, gcc >= 4)
 dnl supports it. This can help reduce the binary size and startup time.
 AX_CHECK_COMPILE_FLAG([-fvisibility=hidden],