diff -uNr gatling-0.13/GNUmakefile gatling-0.13.mod/GNUmakefile
--- gatling-0.13/GNUmakefile	2012-04-19 19:42:36.000000000 +0300
+++ gatling-0.13.mod/GNUmakefile	2020-01-01 23:37:28.967790097 +0200
@@ -6,7 +6,7 @@
 man1dir=$(MANDIR)/man1
 
 TARGETS=gatling httpbench bindbench dl ioerr bench tlsgatling_nofail \
-pthreadbench cgi ptlsgatling_nofail tlsdl_nofail ptlsdl_nofail
+pthreadbench cgi tlsdl_nofail
 TARGETS2=mktestdata mmapbench manymapbench forkbench forksbench
 ALLTARGETS=$(TARGETS) acc hcat referrer hitprofile matchiprange getlinks \
 rellink $(TARGETS2)
@@ -19,13 +19,13 @@
 path = $(subst :, ,$(PATH))
 gcc_path = $(foreach dir,$(path),$(wildcard $(dir)/$(CROSS)gcc))
 ifeq ($(strip $(gcc_path)),)
-CC=$(CROSS)clang
+CC?=$(CROSS)clang
 else
-CC=$(CROSS)gcc
+CC?=$(CROSS)gcc
 endif
 
-CFLAGS=-pipe -Wall
-LDFLAGS=
+CFLAGS?=-pipe -Wall
+LDFLAGS?=
 
 #CFLAGS+=-DSTATE_DEBUG -DMOREDEBUG -DDEBUG_EVENTS -DSMDEBUG
 
@@ -47,10 +47,7 @@
 CFLAGS+=-g -Og
 LDFLAGS+=-g
 else
-CFLAGS+=-O2 -fomit-frame-pointer -I/usr/local/include
-LDFLAGS+=-s
 ifneq ($(DIET),)
-DIET+=-Os
 endif
 endif
 
@@ -81,7 +78,7 @@
 	$(CC) $< -o $@ -I. $(CFLAGS) $(LDFLAGS) $(LDLIBS)
 
 forksbench: forkbench.o
-	$(CC) -static -o $@ forkbench.o $(LDFLAGS) $(LDLIBS)
+	$(CC) -o $@ forkbench.o $(LDFLAGS) $(LDLIBS)
 
 gatling.o tlsgatling ptlsgatling: havesetresuid.h
 
