Don't force -O2.
--- a/Makefile
+++ b/Makefile
@@ -22,7 +22,7 @@ PMPATHD  = /usr/lib/systemd/system-sleep
 
 PKG_CONFIG ?= pkg-config
 
-override CFLAGS  := -O2 -I. -Wall $(shell $(PKG_CONFIG) --cflags glib-2.0) -Wmissing-prototypes -Wmissing-declarations -Wformat-security $(CFLAGS) # -DNOPERFEVENT   # -DHTTPSTATS
+override CFLAGS  := -I. -Wall $(shell $(PKG_CONFIG) --cflags glib-2.0) -Wmissing-prototypes -Wmissing-declarations -Wformat-security $(CFLAGS) # -DNOPERFEVENT   # -DHTTPSTATS
 
 CC_CHECK := $(shell echo | $(CC) -dM -E - | grep -q __clang__ && echo clang || echo gcc)
 ifeq ($(CC_CHECK),gcc)