diff --git a/Makefile.am b/Makefile.am
index 5502de86..5f9e0116 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -25,17 +25,15 @@ endif
 # Set flags for gcc. gcc4 whines abouts silly stuff so it needs slightly
 # different flags.
 if IS_GCC
-CFLAGS += -std=gnu99
+CFLAGS += -std=gnu99 -O2
 if IS_DEBUG
-CFLAGS += -O0 -g
+CFLAGS += -g
 CFLAGS += -Wno-long-long -Wall -W -Wnested-externs -Wformat=2
 CFLAGS += -Wmissing-prototypes -Wstrict-prototypes -Wmissing-declarations
 CFLAGS += -Wwrite-strings -Wshadow -Wpointer-arith -Wsign-compare
 CFLAGS += -Wundef -Wbad-function-cast -Winline -Wcast-align
 CFLAGS += -Wdeclaration-after-statement
 CPPFLAGS += -DDEBUG
-else
-CFLAGS += -O2
 endif
 if IS_GCC4
 CPPFLAGS += -iquote. -I/usr/local/include
@@ -247,7 +245,7 @@ install-exec-hook:
 			>$(srcdir)/tmux.1.mdoc; \
 	else \
 		sed -e "s|@SYSCONFDIR@|$(sysconfdir)|g" $(srcdir)/tmux.1| \
-			$(AWK) -f $(srcdir)/mdoc2man.awk >$(srcdir)/tmux.1.man; \
+			$(AWK) -f$(srcdir)/mdoc2man.awk >$(srcdir)/tmux.1.man; \
 	fi
 	$(MKDIR_P) $(DESTDIR)$(mandir)/man1
 	$(INSTALL_DATA) $(srcdir)/tmux.1.@MANFORMAT@ \