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 <keescook@chromium.org>
This commit is contained in:
Kees Cook 2016-06-17 23:11:12 -07:00
parent d26e941492
commit ed58c0e9ee
3 changed files with 41 additions and 18 deletions

View file

@ -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

View file

@ -23,21 +23,37 @@ ifdef CONFIG_GCC_PLUGINS
export PLUGINCC GCC_PLUGINS_CFLAGS GCC_PLUGIN SANCOV_PLUGIN
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?)
else
$(warning warning: your gcc version does not support plugins, you should upgrade it to gcc 4.5 at least)
endif
endif
else
ifneq ($(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)
$(Q)$(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
@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
endif
endif
@:
# 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
@:

View file

@ -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 <<EOF
#include "gcc-common.h"
@ -13,6 +20,9 @@ EOF
if [ $? -ne 0 ]
then
if [ -n "$SHOW_ERROR" ] ; then
echo "${plugincc}" >&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