diff --git a/Makefile.rules b/Makefile.rules
index affd0fb3598..c1225402c10 100644
--- a/Makefile.rules
+++ b/Makefile.rules
@@ -219,17 +219,21 @@ else
     C.Flags   := -g
     LD.Flags  := -g 
     KEEP_SYMBOLS := 1
-    # Assertions default to ON for debug builds.
-    ENABLE_ASSERTIONS := 1
   endif
 endif
 
-# If this is a debug build or if ENABLE_ASSERTIONS=1 is specified on the make
-# command line, enable assertions.
+# If ENABLE_ASSERTIONS=1 is specified (make command line or configured),
+# then enable assertions by defining the appropriate preprocessor symbols.
 ifdef ENABLE_ASSERTIONS
+  ifdef ENABLE_OPTIMIZED
+  BuildMode := $(BuildMode)+Asserts
+  endif
   CXX.Flags += -D_DEBUG
   C.Flags   += -D_DEBUG
 else
+  ifndef ENABLE_OPTIMIZED
+  BuildMode := $(BuildMode)-Asserts
+  endif
   CXX.Flags += -DNDEBUG
   C.Flags   += -DNDEBUG
 endif
@@ -580,10 +584,9 @@ endif
 #---------------------------------------------------------
 ifeq ($(firstword $(LLVMLIBS)),config)
 LLVM_CONFIG := $(LLVM_SRC_ROOT)/utils/llvm-config/llvm-config 
-LLVMLIBS := $(shell $(LLVM_CONFIG) $(wordlist 2,9999,$(LLVMLIBS)))
-LLVMLIBS := $(patsubst $(PROJ_libdir)/%,%,$(LLVMLIBS))
+LLVMLIBS := $(shell $(LLVM_CONFIG) --libnames $(wordlist 2,9999,$(LLVMLIBS)))
+LLVMLIBS := $(patsubst lib%.a,%.a,$(LLVMLIBS))
 LLVMLIBS := $(patsubst %.o,%,$(LLVMLIBS))
-LLVMLIBS := $(patsubst -l%,%.a,$(LLVMLIBS))
 endif
 
 ifeq ($(LLVMLIBS),JIT)
@@ -1529,7 +1532,7 @@ $(DistDir)/.makedistdir: $(DistSources)
 	  $(EchoCmd) Removing old $(DistDir) ; \
 	  $(RM) -rf $(DistDir); \
 	  $(EchoCmd) Making 'all' to verify build ; \
-	  $(MAKE) all ; \
+	  $(MAKE) ENABLE_OPTIMIZED=1 ENABLE_ASSERTIONS=1 all ; \
 	fi
 	$(Echo) Building Distribution Directory $(DistDir)
 	$(Verb) $(MKDIR) $(DistDir) 
@@ -1590,8 +1593,8 @@ $(DistDir)/.makedistdir: $(DistSources)
 	  if test "$$subdir" \!= "." ; then \
 	    new_distdir="$(DistDir)/$$subdir" ; \
 	    test -d "$$new_distdir" || $(MKDIR) "$$new_distdir" || exit 1; \
-	    ( cd $$subdir && $(MAKE) DistDir="$$new_distdir" distdir ) || \
-	    exit 1; \
+	    ( cd $$subdir && $(MAKE) ENABLE_OPTIMIZED=1 ENABLE_ASSERTIONS=1 \
+	      DistDir="$$new_distdir" distdir ) || exit 1; \
 	  fi; \
 	done
 	$(Verb) if test "$(DistDir)" = "$(TopDistDir)" ; then \