Re: [PATCH v3 06/12] Makefile: Split $(FLAGS) into cpp and cc components

On Sat, May 16, 2026 at 05:45:54PM +0200, Stefano Brivio wrote:

On Tue, 12 May 2026 15:52:50 +1000 David Gibson wrote:

...

The $(FLAGS) variable contains mandatory compiler flags that should not be overridden. However, it contains a mixture of flags for the preprocessor and for the compiler proper. That's causing some inconvenience for other Makefile cleanups, so split it into $(BASE_CPPFLAGS) and $(BASE_CFLAGS) variables.

Signed-off-by: David Gibson --- Makefile | 40 ++++++++++++++++++++++++---------------- 1 file changed, 24 insertions(+), 16 deletions(-)

diff --git a/Makefile b/Makefile index a8f8d06e..697f229f 100644 --- a/Makefile +++ b/Makefile @@ -30,12 +30,17 @@ ifeq ($(shell $(CC) -O2 -dM -E - < /dev/null 2>&1 | grep ' _FORTIFY_SOURCE ' > / FORTIFY_FLAG := -D_FORTIFY_SOURCE=2 endif

-FLAGS := -Wall -Wextra -Wno-format-zero-length -Wformat-security -FLAGS += -pedantic -std=c11 -D_XOPEN_SOURCE=700 -D_GNU_SOURCE -FLAGS += $(FORTIFY_FLAG) -O2 -pie -fPIE -FLAGS += -DPAGE_SIZE=$(shell getconf PAGE_SIZE) -FLAGS += -DVERSION=\"$(VERSION)\" -FLAGS += -DDUAL_STACK_SOCKETS=$(DUAL_STACK_SOCKETS) +# Mandatory preprocessor flags that won't be overridden with $(CPPFLAGS) +# FIXME: Could some of these be default, rather than required? +BASE_CPPFLAGS := -D_XOPEN_SOURCE=700 -D_GNU_SOURCE $(FORTIFY_FLAG) +BASE_CPPFLAGS += -DPAGE_SIZE=$(shell getconf PAGE_SIZE) +BASE_CPPFLAGS += -DVERSION=\"$(VERSION)\" +BASE_CPPFLAGS += -DDUAL_STACK_SOCKETS=$(DUAL_STACK_SOCKETS) + +# Mandatory compiler flags that won't be overridden with $(CFLAGS) +# FIXME: Could some of these be default, rather than required? +BASE_CFLAGS := -std=c11 -pie -fPIE -O2 +BASE_CFLAGS += -pedantic -Wall -Wextra -Wno-format-zero-length -Wformat-security

PASST_SRCS = arch.c arp.c bitmap.c checksum.c conf.c dhcp.c dhcpv6.c \ epoll_ctl.c flow.c fwd.c fwd_rule.c icmp.c igmp.c inany.c iov.c ip.c \ @@ -62,11 +67,11 @@ PASST_REPAIR_HEADERS = linux_dep.h

C := \#include \nint main(){int a=getrandom(0, 0, 0);} ifeq ($(shell printf "$(C)" | $(CC) -S -xc - -o - >/dev/null 2>&1; echo $$?),0) - FLAGS += -DHAS_GETRANDOM + BASE_CPPFLAGS += -DHAS_GETRANDOM endif

ifeq ($(shell :|$(CC) -fstack-protector-strong -S -xc - -o - >/dev/null 2>&1; echo $$?),0) - FLAGS += -fstack-protector-strong + BASE_CFLAGS += -fstack-protector-strong endif

prefix ?= /usr/local @@ -89,7 +94,8 @@ endif

all: $(BIN) $(MANPAGES) docs

-static: FLAGS += -static -DGLIBC_NO_STATIC_NSS +static: BASE_CPPFLAGS += -DGLIBC_NO_STATIC_NSS +static: BASE_CFLAGS += -static

Trailing whitespace I fixed up on merge.

Oops, thanks! -- David Gibson (he or they) | I'll have my music baroque, and my code david AT gibson.dropbear.id.au | minimalist, thank you, not the other way | around. http://www.ozlabs.org/~dgibson