experimental/cmake-improvement

set CMAKE_LIBRARY_PATH, CMAKE_INCLUDE_PATH based on NIX_CFLAGS_COMPILE and
NIX_LDFLAGS so that cmake's find_library like functions find all the libraries
gcc knows about thanks to the gcc wrapper

This is particular useful with myEnvFun which then also sets those CMAKE_* env
variables.`

Because setup.sh has to change this causes many rebuilds - thus it should be
included in a stdenv-update like branch

Also cmake builds in parallel perfectly fine

update cmake to latest minor number, I didn't change the patches,
just reapplied them manually recordin a new patch

pkgs/development/tools/build-managers/cmake/setup-hook.sh

@@ -56,3 +56,20 @@ if [ -n "$crossConfig" ]; then
 else
     envHooks+=(addCMakeParams)
 fi
+
+make_cmake_find_libs(){
+  for flag in $NIX_CFLAGS_COMPILE $NIX_LDFLAGS; do
+    case $flag in
+      -I*)
+        export CMAKE_INCLUDE_PATH="$CMAKE_INCLUDE_PATH${CMAKE_INCLUDE_PATH:+:}${flag:2}"
+        ;;
+      -L*)
+        export CMAKE_LIBRARY_PATH="$CMAKE_LIBRARY_PATH${CMAKE_LIBRARY_PATH:+:}${flag:2}"
+        ;;
+    esac
+  done
+}
+
+# not using setupHook, because it could be a setupHook adding additional
+# include flags to NIX_CFLAGS_COMPILE
+postHooks+=(make_cmake_find_libs)