From ed58c0e9eefef517aa5a547b78658e2ab4422232 Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Fri, 17 Jun 2016 23:11:12 -0700 Subject: [PATCH] gcc-plugins: abort builds cleanly when not supported When the compiler doesn't support gcc plugins (either due to missing headers or too old a version), report the problem and abort the build instead of emitting a warning and letting the build founder with arcane compiler errors. Signed-off-by: Kees Cook --- Makefile | 7 ------- scripts/Makefile.gcc-plugins | 34 +++++++++++++++++++++++++--------- scripts/gcc-plugin.sh | 14 ++++++++++++++ 3 files changed, 39 insertions(+), 16 deletions(-) diff --git a/Makefile b/Makefile index 70de1448c571..8c504f324154 100644 --- a/Makefile +++ b/Makefile @@ -635,13 +635,6 @@ endif # Tell gcc to never replace conditional load with a non-conditional one KBUILD_CFLAGS += $(call cc-option,--param=allow-store-data-races=0) -PHONY += gcc-plugins -gcc-plugins: scripts_basic -ifdef CONFIG_GCC_PLUGINS - $(Q)$(MAKE) $(build)=scripts/gcc-plugins -endif - @: - include scripts/Makefile.gcc-plugins ifdef CONFIG_READABLE_ASM diff --git a/scripts/Makefile.gcc-plugins b/scripts/Makefile.gcc-plugins index 5e22b60589c1..bbca1f46f6e4 100644 --- a/scripts/Makefile.gcc-plugins +++ b/scripts/Makefile.gcc-plugins @@ -23,21 +23,37 @@ ifdef CONFIG_GCC_PLUGINS export PLUGINCC GCC_PLUGINS_CFLAGS GCC_PLUGIN SANCOV_PLUGIN + ifneq ($(PLUGINCC),) + # SANCOV_PLUGIN can be only in CFLAGS_KCOV because avoid duplication. + GCC_PLUGINS_CFLAGS := $(filter-out $(SANCOV_PLUGIN), $(GCC_PLUGINS_CFLAGS)) + endif + + KBUILD_CFLAGS += $(GCC_PLUGINS_CFLAGS) + GCC_PLUGIN := $(gcc-plugin-y) +endif + +# If plugins aren't supported, abort the build before hard-to-read compiler +# errors start getting spewed by the main build. +PHONY += gcc-plugins-check +gcc-plugins-check: FORCE +ifdef CONFIG_GCC_PLUGINS ifeq ($(PLUGINCC),) ifneq ($(GCC_PLUGINS_CFLAGS),) ifeq ($(call cc-ifversion, -ge, 0405, y), y) - PLUGINCC := $(shell $(CONFIG_SHELL) -x $(srctree)/scripts/gcc-plugin.sh "$(__PLUGINCC)" "$(HOSTCXX)" "$(CC)") - $(warning warning: your gcc installation does not support plugins, perhaps the necessary headers are missing?) + $(Q)$(srctree)/scripts/gcc-plugin.sh --show-error "$(__PLUGINCC)" "$(HOSTCXX)" "$(CC)" || true + @echo "Cannot use CONFIG_GCC_PLUGINS: your gcc installation does not support plugins, perhaps the necessary headers are missing?" >&2 && exit 1 else - $(warning warning: your gcc version does not support plugins, you should upgrade it to gcc 4.5 at least) + @echo "Cannot use CONFIG_GCC_PLUGINS: your gcc version does not support plugins, you should upgrade it to at least gcc 4.5" >&2 && exit 1 endif endif - else - # SANCOV_PLUGIN can be only in CFLAGS_KCOV because avoid duplication. - GCC_PLUGINS_CFLAGS := $(filter-out $(SANCOV_PLUGIN), $(GCC_PLUGINS_CFLAGS)) endif +endif + @: - KBUILD_CFLAGS += $(GCC_PLUGINS_CFLAGS) - GCC_PLUGIN := $(gcc-plugin-y) - +# Actually do the build, if requested. +PHONY += gcc-plugins +gcc-plugins: scripts_basic gcc-plugins-check +ifdef CONFIG_GCC_PLUGINS + $(Q)$(MAKE) $(build)=scripts/gcc-plugins endif + @: diff --git a/scripts/gcc-plugin.sh b/scripts/gcc-plugin.sh index fb9207565471..b65224bfb847 100755 --- a/scripts/gcc-plugin.sh +++ b/scripts/gcc-plugin.sh @@ -1,5 +1,12 @@ #!/bin/sh srctree=$(dirname "$0") + +SHOW_ERROR= +if [ "$1" = "--show-error" ] ; then + SHOW_ERROR=1 + shift || true +fi + gccplugins_dir=$($3 -print-file-name=plugin) plugincc=$($1 -E -x c++ - -o /dev/null -I"${srctree}"/gcc-plugins -I"${gccplugins_dir}"/include 2>&1 <&2 + fi exit 1 fi @@ -48,4 +58,8 @@ then echo "$2" exit 0 fi + +if [ -n "$SHOW_ERROR" ] ; then + echo "${plugincc}" >&2 +fi exit 1 -- 2.20.1