This patch is by Michael Mair-Keimberger, as part of bug 339657. It
teaches the Makefile to support the user's LDFLAGS.

Gentoo-Bug: https://bugs.gentoo.org/339657

--- a/Makefile
+++ b/Makefile
@@ -9,7 +9,7 @@
 IMLIB_LIB ?= 
 PLUGIN_DIR ?= /usr/local/lib/gkrellm2/plugins
 
-FLAGS = -O2 -Wall -fPIC $(GTK_INCLUDE) $(IMLIB_INCLUDE)
+FLAGS = -fPIC $(GTK_INCLUDE) $(IMLIB_INCLUDE)
 LIBS = $(GTK_LIB) $(IMLIB_LIB)
 LFLAGS = -shared -lpthread
 
@@ -22,8 +22,8 @@
 FLAGS += -DPACKAGE="\"$(PACKAGE)\"" 
 export PACKAGE LOCALEDIR
 
-CC ?= gcc 
-CC += $(CFLAGS) $(FLAGS)
+
+CC = $(CC)
 
 INSTALL = install -c
 INSTALL_PROGRAM = $(INSTALL) -s
@@ -32,8 +32,11 @@
 
 all:	$(BIN_FILENAME).so
 
+%.o: %.c
+	$(CC) $(CFLAGS) $(LDFLAGS) $(FLAGS) -c -o $@ $<
+
 $(BIN_FILENAME).so: $(OBJS)
-	$(CC) $(OBJS) -o $(BIN_FILENAME).so $(LFLAGS) $(LIBS)
+	$(CC) $(CFLAGS) $(LDFLAGS) $(FLAGS) $(OBJS) -o $(BIN_FILENAME).so $(LFLAGS) $(LIBS)
 
 clean:
 	rm -f *.o core *.so* *.bak *~