Check that we do not revert 3rdParty by accident

Some people checked in changes to 3rdParty that were not intended.
This commit checks that all new commits use the old hash or a more
recent one.

Author: sjoelund

Makefile.common

@@ -450,5 +450,6 @@ git-sanity-check: git-clean
 	test "./Compiler/boot/bootstrap-sources.tar.xz" = "`find . -type f -size +684k | grep -v 3rdParty`"
 	for commit in `git rev-list origin/master..HEAD`; do \
 	  (! git ls-tree --name-only -r $$commit | egrep "(.*[.](html|png|svg|o|so|la|stamp|a|dll|exe|cab|lnk|msi|log|class|jar|pyc|db|zip|DS_Store|pdf|tex|md5|dep)$$)|SimulationRuntime/cpp/Doc") || exit 1; \
+	  (MASTER=`git ls-tree origin/master 3rdParty | grep -E -o  "[0-9a-f]{40}"` && HASH=`git ls-tree $$commit 3rdParty | grep -E -o  "[0-9a-f]{40}"` && cd 3rdParty && (test -z "`git rev-list $$HASH..$$MASTER`" || echo "ERROR: Commit is reverting 3rdParty to an older commit. This is probably not intended.")) \
 	done
 	! (git rev-list origin/master..HEAD | xargs git grep "Generated by Susan" -- Compiler/Template)