Merge branch 'cxx-checks-warning-match' into release-3.14

Merge-request: !3075

Source/Checks/cm_cxx_features.cmake

@@ -27,7 +27,7 @@ function(cm_check_cxx_feature name)
     # Filter out xcodebuild warnings.
     string(REGEX REPLACE "[^\n]* xcodebuild\\[[0-9]*:[0-9]*\\] warning: [^\n]*" "" check_output "${check_output}")
     # If using the feature causes warnings, treat it as broken/unavailable.
-    if(check_output MATCHES "[Ww]arning")
+    if(check_output MATCHES "(^|[ :])[Ww][Aa][Rr][Nn][Ii][Nn][Gg]")
       set(CMake_HAVE_CXX_${FEATURE} OFF CACHE INTERNAL "TRY_COMPILE" FORCE)
     endif()
     if(CMake_HAVE_CXX_${FEATURE})