Define ENABLE_CLANG_EXAMPLES instead of relying on BUILD_EXAMPLES

This is a further build fix attempt for r198747 on some Makefile builders where
the value wasn't set at all.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@198764 91177308-0d34-0410-b5e6-96231b3b80d8

Makefile

@@ -23,6 +23,12 @@ ifeq ($(BUILD_EXAMPLES),1)
 endif
 endif
 
+ifeq ($(BUILD_EXAMPLES),1)
+  ENABLE_CLANG_EXAMPLES := 1
+else
+  ENABLE_CLANG_EXAMPLES := 0
+endif
+
 ifeq ($(MAKECMDGOALS),libs-only)
   DIRS := $(filter-out tools docs, $(DIRS))
   OPTIONAL_DIRS :=

test/Makefile

@@ -49,7 +49,7 @@ lit.site.cfg: FORCE
 	@$(ECHOPATH) s=@ENABLE_CLANG_ARCMT@=$(ENABLE_CLANG_ARCMT)=g >> lit.tmp
 	@$(ECHOPATH) s=@ENABLE_CLANG_REWRITER@=$(ENABLE_CLANG_REWRITER)=g >> lit.tmp
 	@$(ECHOPATH) s=@ENABLE_CLANG_STATIC_ANALYZER@=$(ENABLE_CLANG_STATIC_ANALYZER)=g >> lit.tmp
-	@$(ECHOPATH) s=@ENABLE_CLANG_EXAMPLES@=$(BUILD_EXAMPLES)=g >> lit.tmp
+	@$(ECHOPATH) s=@ENABLE_CLANG_EXAMPLES@=$(ENABLE_CLANG_EXAMPLES)=g >> lit.tmp
 	@sed -f lit.tmp $(PROJ_SRC_DIR)/lit.site.cfg.in > $@
 	@-rm -f lit.tmp