From 9de4f9592928029a65f628fa109a4761282d8466 Mon Sep 17 00:00:00 2001 From: Philipp Tomsich Date: Mon, 14 May 2018 15:22:06 +0200 Subject: [PATCH] Makefile: adopt --std=gnu11 for HOSTCFLAGS on Linux Following the conversion of the SPDX license tags, a number of files compiled with -pedantic now generate warnings similar to the following for using C99-style '//' comments in ISO C90 code: tools/gen_eth_addr.c:1:1: warning: C++ style comments are not allowed in ISO C90 // SPDX-License-Identifier: GPL-2.0+ ^ The SPDX comment-style change means that these files have adopted C99, so need to change the language-standard to --std=gnu99 or --std=gnu11 to let the compiler know this. As we now require GCC 6 or newer for the cross-compiler, the project has implicitly moved the project to GNU11: let older GCC versions on various Linux distros know to treat our host tools as GNU11 as well. References: commit 83d290c56fab ("SPDX: Convert all of our single license tags to Linux Kernel style") Signed-off-by: Philipp Tomsich Reviewed-by: Tom Rini --- Makefile | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/Makefile b/Makefile index f31ee60..d08fb6a 100644 --- a/Makefile +++ b/Makefile @@ -258,6 +258,15 @@ HOSTCFLAGS = -Wall -Wstrict-prototypes -O2 -fomit-frame-pointer \ $(if $(CONFIG_TOOLS_DEBUG),-g) HOSTCXXFLAGS = -O2 +# With the move to GCC 6, we have implicitly upgraded our language +# standard to GNU11 (see https://gcc.gnu.org/gcc-5/porting_to.html). +# Some Linux distributions (including RHEL7, SLES13, Debian 8) still +# have older compilers as their default, so we make it explicit for +# these that our host tools are GNU11 (i.e. C11 w/ GNU extensions). +ifeq ($(HOSTOS),linux) +HOSTCFLAGS += --std=gnu11 +endif + ifeq ($(HOSTOS),cygwin) HOSTCFLAGS += -ansi endif -- 2.7.4