diff --git a/src/c_make.gen b/src/c_make.gen
index 414dead..84c3030 100644
--- a/src/c_make.gen
+++ b/src/c_make.gen
@@ -200,45 +200,12 @@ LOCAL_SYS_INC=$(SEP_PATH)/../SYS/inc
 #### Do not redefine if (a) passed in on command line, or (b)
 #### defined in an environment variable.
 
-ifneq "$(origin CC)" "environment"
-CC      = cc
-endif
-
-ifneq "$(origin CPPFLAGS)" "environment"
-CPPFLAGS=
-endif
-
-ifneq "$(origin CFLAGS)" "environment"
-CFLAGS  =
-endif
-
-ifneq "$(origin CDEFS)" "environment"
-CDEFS  =
-endif
-
-ifneq "$(origin CXX)" "environment"
-CXX	= g++
-endif
-
-ifneq "$(origin CXXFLAGS)" "environment"
-CXXFLAGS=
-endif
-
-ifneq "$(origin CXXDEFS)" "environment"
-CXXDEFS= -D__cplusplus
-endif
-
-ifneq "$(origin AR)" "environment"
-AR      = ar
-endif
-
-ifneq "$(origin ARFLAGS)" "environment"
-ARFLAGS = rvs
-endif
-
-ifneq "$(origin LDFLAGS)" "environment"
-LDFLAGS =
-endif
+CC      ?= cc
+CXX	?= g++
+CXXFLAGS ?=
+CXXDEFS = -D__cplusplus
+AR      ?= ar
+ARFLAGS ?= rvs
 
 #### Delete default suffix rules
 .SUFFIXES:
@@ -359,13 +326,13 @@ $(PROGS):
 	  cd $(LOCAL_OBJ); \
 	    if $(CC) -o $(LOCAL_BIN)/$(notdir $@) $(LDFLAGS) \
                $(LD_DIRS) $(filter-out lib%.a, $+) \
-	       $(patsubst lib%.a, -l%, $(filter lib%.a, $+)) ; then \
+	       $(patsubst lib%.a, -l%, $(filter lib%.a, $+)) $(LIBS) ; then \
 			true; else rm -f $(LOCAL_BIN)/$(notdir $@); fi; \
 	else \
 	  cd $(LOCAL_OBJ); \
 	    if $(CXX) -o $(LOCAL_BIN)/$(notdir $@) $(LDFLAGS) \
                $(LD_DIRS) $(filter-out lib%.a, $+) \
-	       $(patsubst lib%.a, -l%, $(filter lib%.a, $+)) ; then \
+	       $(patsubst lib%.a, -l%, $(filter lib%.a, $+)) $(LIBS) ; then \
 			true; else rm -f $(LOCAL_BIN)/$(notdir $@); fi; \
 	fi ;
 
diff --git a/src/c_make.glm b/src/c_make.glm
index 0decc17..b82131c 100644
--- a/src/c_make.glm
+++ b/src/c_make.glm
@@ -8,10 +8,7 @@ include $(LOCAL_WORK)/src/c_make.gen
 
 SUBDIRS = Common ICM Glimmer Util
 
-CFLAGS = -g -Wall
-CXXFLAGS = -g -Wall
-
-LDFLAGS = -g -lm
+LIBS = -lm
 
 
 #AS_BUILD_DIR =$(LOCAL_WORK)