From: Andrea Bolognani <eof@kiyuko.org>
Date: Sun, 31 Jul 2016 16:56:27 +0000 (+0200)
Subject: linux: Enable PIE
X-Git-Url: https://code.delx.au/spectrwm/commitdiff_plain/092e5c269ffa08e9d174100a06d0d56ffcc85b69

linux: Enable PIE

PIE (position-independent executables) is a security feature
that has been made reasonably cheap by recent improvements in
GCC; as a result, more and more Linux distributions are pushing
for its adoption.

Unfortunately, PIE and PIC are not compatible, so we have to
manage the CFLAGS and LDFLAGS used to compile the library and
the executable indipendently.
---

diff --git a/linux/Makefile b/linux/Makefile
index 74f648a..bad2b0b 100644
--- a/linux/Makefile
+++ b/linux/Makefile
@@ -17,27 +17,31 @@ ifneq ("${BUILDVERSION}", "")
 MAINT_CPPFLAGS += -DSPECTRWM_BUILDSTR=\"$(BUILDVERSION)\"
 endif
 
+BIN_CFLAGS   = -fPIE
+BIN_LDFLAGS  = -fPIE -pie
 BIN_CPPFLAGS = $(shell pkg-config --cflags x11 x11-xcb xcb-icccm xcb-keysyms xcb-randr xcb-util xcb-xtest xcursor xft)
 BIN_LDLIBS   = $(shell pkg-config --libs   x11 x11-xcb xcb-icccm xcb-keysyms xcb-randr xcb-util xcb-xtest xcursor xft)
+LIB_CFLAGS   = -fPIC
+LIB_LDFLAGS  = -fPIC -shared
 LIB_CPPFLAGS = $(shell pkg-config --cflags x11)
 LIB_LDLIBS   = $(shell pkg-config --libs   x11) -ldl
 
 all: spectrwm libswmhack.so.$(LIBVERSION)
 
 spectrwm: spectrwm.o linux.o
-	$(CC) $(MAINT_LDFLAGS) $(LDFLAGS) -o $@ $+ $(BIN_LDLIBS) $(LDLIBS)
+	$(CC) $(MAINT_LDFLAGS) $(BIN_LDFLAGS) $(LDFLAGS) -o $@ $+ $(BIN_LDLIBS) $(LDLIBS)
 
 spectrwm.o: ../spectrwm.c ../version.h tree.h util.h
-	$(CC) $(MAINT_CFLAGS) $(CFLAGS) $(MAINT_CPPFLAGS) $(BIN_CPPFLAGS) $(CPPFLAGS) -c -o $@ $<
+	$(CC) $(MAINT_CFLAGS) $(BIN_CFLAGS) $(CFLAGS) $(MAINT_CPPFLAGS) $(BIN_CPPFLAGS) $(CPPFLAGS) -c -o $@ $<
 
 linux.o: linux.c util.h
-	$(CC) $(MAINT_CFLAGS) $(CFLAGS) $(MAINT_CPPFLAGS) $(BIN_CPPFLAGS) $(CPPFLAGS) -c -o $@ $<
+	$(CC) $(MAINT_CFLAGS) $(BIN_CFLAGS) $(CFLAGS) $(MAINT_CPPFLAGS) $(BIN_CPPFLAGS) $(CPPFLAGS) -c -o $@ $<
 
 libswmhack.so.$(LIBVERSION): swm_hack.so
-	$(CC) $(MAINT_LDFLAGS) $(LDFLAGS) -Wl,-soname,$@ -shared -fPIC -o $@ $+ $(LIB_LDLIBS) $(LDLIBS)
+	$(CC) $(MAINT_LDFLAGS) $(LIB_LDFLAGS) $(LDFLAGS) -Wl,-soname,$@ -o $@ $+ $(LIB_LDLIBS) $(LDLIBS)
 
 swm_hack.so: ../lib/swm_hack.c
-	$(CC) $(MAINT_CFLAGS) $(CFLAGS) $(MAINT_CPPFLAGS) $(LIB_CPPFLAGS) $(CPPFLAGS) -fPIC -c -o $@ $<
+	$(CC) $(MAINT_CFLAGS) $(LIB_CFLAGS) $(CFLAGS) $(MAINT_CPPFLAGS) $(LIB_CPPFLAGS) $(CPPFLAGS) -c -o $@ $<
 
 clean:
 	rm -f spectrwm *.o libswmhack.so.* *.so