On Sun, Mar 29, 2020 at 08:08:32PM +0900, Masahiro Yamada wrote: > Nobody was opposed to raising minimum GCC version to 4.8 [1] > So, we will drop GCC <= 4.7 support sooner or later. > > We always use C++ compiler for building plugins for GCC >= 4.8. > > This commit drops the plugin support for GCC <= 4.7 a bit earlier, > which allows us to dump lots of code. > > [1] https://lkml.org/lkml/2020/1/23/545 > > Signed-off-by: Masahiro Yamada <masahiroy@xxxxxxxxxx> Thanks for getting this cleaned up! I look forward to the 4.8 version bump. :) Acked-by: Kees Cook <keescook@xxxxxxxxxxxx> -Kees > --- > > This patch depends on this: > https://patchwork.kernel.org/patch/11456871/ > > scripts/Kconfig.include | 3 -- > scripts/Makefile.build | 2 +- > scripts/Makefile.clean | 1 - > scripts/Makefile.host | 23 +-------------- > scripts/gcc-plugin.sh | 55 +++--------------------------------- > scripts/gcc-plugins/Kconfig | 12 ++------ > scripts/gcc-plugins/Makefile | 21 ++++---------- > 7 files changed, 14 insertions(+), 103 deletions(-) > > diff --git a/scripts/Kconfig.include b/scripts/Kconfig.include > index 496d11c92c97..033f6efd92d3 100644 > --- a/scripts/Kconfig.include > +++ b/scripts/Kconfig.include > @@ -42,9 +42,6 @@ $(error-if,$(failure,command -v $(LD)),linker '$(LD)' not found) > # Fail if the linker is gold as it's not capable of linking the kernel proper > $(error-if,$(success, $(LD) -v | grep -q gold), gold linker '$(LD)' not supported) > > -# gcc version including patch level > -gcc-version := $(shell,$(srctree)/scripts/gcc-version.sh $(CC)) > - > # machine bit flags > # $(m32-flag): -m32 if the compiler supports it, or an empty string otherwise. > # $(m64-flag): -m64 if the compiler supports it, or an empty string otherwise. > diff --git a/scripts/Makefile.build b/scripts/Makefile.build > index 356601994f3a..9fcbfac15d1d 100644 > --- a/scripts/Makefile.build > +++ b/scripts/Makefile.build > @@ -46,7 +46,7 @@ include $(kbuild-file) > include scripts/Makefile.lib > > # Do not include host rules unless needed > -ifneq ($(hostprogs)$(hostlibs-y)$(hostlibs-m)$(hostcxxlibs-y)$(hostcxxlibs-m),) > +ifneq ($(hostprogs)$(hostcxxlibs-y)$(hostcxxlibs-m),) > include scripts/Makefile.host > endif > > diff --git a/scripts/Makefile.clean b/scripts/Makefile.clean > index 1e4206566a82..075f0cc2d8d7 100644 > --- a/scripts/Makefile.clean > +++ b/scripts/Makefile.clean > @@ -30,7 +30,6 @@ subdir-ymn := $(addprefix $(obj)/,$(subdir-ymn)) > __clean-files := $(extra-y) $(extra-m) $(extra-) \ > $(always) $(always-y) $(always-m) $(always-) $(targets) $(clean-files) \ > $(hostprogs) $(hostprogs-y) $(hostprogs-m) $(hostprogs-) \ > - $(hostlibs-y) $(hostlibs-m) $(hostlibs-) \ > $(hostcxxlibs-y) $(hostcxxlibs-m) > > __clean-files := $(filter-out $(no-clean-files), $(__clean-files)) > diff --git a/scripts/Makefile.host b/scripts/Makefile.host > index 3b7121d43324..2045855d0b75 100644 > --- a/scripts/Makefile.host > +++ b/scripts/Makefile.host > @@ -39,7 +39,6 @@ $(obj)/%.tab.c $(obj)/%.tab.h: $(src)/%.y FORCE > # They are linked as C++ code to the executable qconf > > __hostprogs := $(sort $(hostprogs)) > -host-cshlib := $(sort $(hostlibs-y) $(hostlibs-m)) > host-cxxshlib := $(sort $(hostcxxlibs-y) $(hostcxxlibs-m)) > > # C code > @@ -63,7 +62,6 @@ host-cxxmulti := $(foreach m,$(__hostprogs),$(if $($(m)-cxxobjs),$(m))) > host-cxxobjs := $(sort $(foreach m,$(host-cxxmulti),$($(m)-cxxobjs))) > > # Object (.o) files used by the shared libaries > -host-cshobjs := $(sort $(foreach m,$(host-cshlib),$($(m:.so=-objs)))) > host-cxxshobjs := $(sort $(foreach m,$(host-cxxshlib),$($(m:.so=-objs)))) > > host-csingle := $(addprefix $(obj)/,$(host-csingle)) > @@ -71,9 +69,7 @@ host-cmulti := $(addprefix $(obj)/,$(host-cmulti)) > host-cobjs := $(addprefix $(obj)/,$(host-cobjs)) > host-cxxmulti := $(addprefix $(obj)/,$(host-cxxmulti)) > host-cxxobjs := $(addprefix $(obj)/,$(host-cxxobjs)) > -host-cshlib := $(addprefix $(obj)/,$(host-cshlib)) > host-cxxshlib := $(addprefix $(obj)/,$(host-cxxshlib)) > -host-cshobjs := $(addprefix $(obj)/,$(host-cshobjs)) > host-cxxshobjs := $(addprefix $(obj)/,$(host-cxxshobjs)) > > ##### > @@ -140,13 +136,6 @@ quiet_cmd_host-cxxobjs = HOSTCXX $@ > $(host-cxxobjs): $(obj)/%.o: $(src)/%.cc FORCE > $(call if_changed_dep,host-cxxobjs) > > -# Compile .c file, create position independent .o file > -# host-cshobjs -> .o > -quiet_cmd_host-cshobjs = HOSTCC -fPIC $@ > - cmd_host-cshobjs = $(HOSTCC) $(hostc_flags) -fPIC -c -o $@ $< > -$(host-cshobjs): $(obj)/%.o: $(src)/%.c FORCE > - $(call if_changed_dep,host-cshobjs) > - > # Compile .c file, create position independent .o file > # Note that plugin capable gcc versions can be either C or C++ based > # therefore plugin source files have to be compilable in both C and C++ mode. > @@ -157,16 +146,6 @@ quiet_cmd_host-cxxshobjs = HOSTCXX -fPIC $@ > $(host-cxxshobjs): $(obj)/%.o: $(src)/%.c FORCE > $(call if_changed_dep,host-cxxshobjs) > > -# Link a shared library, based on position independent .o files > -# *.o -> .so shared library (host-cshlib) > -quiet_cmd_host-cshlib = HOSTLLD -shared $@ > - cmd_host-cshlib = $(HOSTCC) $(KBUILD_HOSTLDFLAGS) -shared -o $@ \ > - $(addprefix $(obj)/, $($(target-stem)-objs)) \ > - $(KBUILD_HOSTLDLIBS) $(HOSTLDLIBS_$(target-stem).so) > -$(host-cshlib): FORCE > - $(call if_changed,host-cshlib) > -$(call multi_depend, $(host-cshlib), .so, -objs) > - > # Link a shared library, based on position independent .o files > # *.o -> .so shared library (host-cxxshlib) > quiet_cmd_host-cxxshlib = HOSTLLD -shared $@ > @@ -178,4 +157,4 @@ $(host-cxxshlib): FORCE > $(call multi_depend, $(host-cxxshlib), .so, -objs) > > targets += $(host-csingle) $(host-cmulti) $(host-cobjs)\ > - $(host-cxxmulti) $(host-cxxobjs) $(host-cshlib) $(host-cshobjs) $(host-cxxshlib) $(host-cxxshobjs) > + $(host-cxxmulti) $(host-cxxobjs) $(host-cxxshlib) $(host-cxxshobjs) > diff --git a/scripts/gcc-plugin.sh b/scripts/gcc-plugin.sh > index d3caefe53eab..b79fd0bea838 100755 > --- a/scripts/gcc-plugin.sh > +++ b/scripts/gcc-plugin.sh > @@ -1,49 +1,14 @@ > #!/bin/sh > # SPDX-License-Identifier: GPL-2.0 > -srctree=$(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" > -#if BUILDING_GCC_VERSION >= 4008 || defined(ENABLE_BUILD_WITH_CXX) > -#warning $2 CXX > -#else > -#warning $1 CC > -#endif > -EOF > -) > > -if [ $? -ne 0 ] > -then > - if [ -n "$SHOW_ERROR" ] ; then > - echo "${plugincc}" >&2 > - fi > - exit 1 > -fi > +set -e > > -case "$plugincc" in > - *"$1 CC"*) > - echo "$1" > - exit 0 > - ;; > - > - *"$2 CXX"*) > - # the c++ compiler needs another test, see below > - ;; > +srctree=$(dirname "$0") > > - *) > - exit 1 > - ;; > -esac > +gccplugins_dir=$($* -print-file-name=plugin) > > # we need a c++ compiler that supports the designated initializer GNU extension > -plugincc=$($2 -c -x c++ -std=gnu++98 - -fsyntax-only -I"${srctree}"/gcc-plugins -I"${gccplugins_dir}"/include 2>&1 <<EOF > +$HOSTCC -c -x c++ -std=gnu++98 - -fsyntax-only -I $srctree/gcc-plugins -I $gccplugins_dir/include 2>/dev/null <<EOF > #include "gcc-common.h" > class test { > public: > @@ -52,15 +17,3 @@ public: > .test = 1 > }; > EOF > -) > - > -if [ $? -eq 0 ] > -then > - echo "$2" > - exit 0 > -fi > - > -if [ -n "$SHOW_ERROR" ] ; then > - echo "${plugincc}" >&2 > -fi > -exit 1 > diff --git a/scripts/gcc-plugins/Kconfig b/scripts/gcc-plugins/Kconfig > index 7b63c819610c..a857d69322b4 100644 > --- a/scripts/gcc-plugins/Kconfig > +++ b/scripts/gcc-plugins/Kconfig > @@ -1,13 +1,4 @@ > # SPDX-License-Identifier: GPL-2.0-only > -preferred-plugin-hostcc := $(if-success,[ $(gcc-version) -ge 40800 ],$(HOSTCXX),$(HOSTCC)) > - > -config PLUGIN_HOSTCC > - string > - default "$(shell,$(srctree)/scripts/gcc-plugin.sh "$(preferred-plugin-hostcc)" "$(HOSTCXX)" "$(CC)")" if CC_IS_GCC > - help > - Host compiler used to build GCC plugins. This can be $(HOSTCXX), > - $(HOSTCC), or a null string if GCC plugin is unsupported. > - > config HAVE_GCC_PLUGINS > bool > help > @@ -17,7 +8,8 @@ config HAVE_GCC_PLUGINS > menuconfig GCC_PLUGINS > bool "GCC plugins" > depends on HAVE_GCC_PLUGINS > - depends on PLUGIN_HOSTCC != "" > + depends on CC_IS_GCC && GCC_VERSION >= 40800 > + depends on $(success,$(srctree)/scripts/gcc-plugin.sh $(CC)) > default y > help > GCC plugins are loadable modules that provide extra features to the > diff --git a/scripts/gcc-plugins/Makefile b/scripts/gcc-plugins/Makefile > index efff00959a9c..f22858b2c3d6 100644 > --- a/scripts/gcc-plugins/Makefile > +++ b/scripts/gcc-plugins/Makefile > @@ -1,18 +1,9 @@ > # SPDX-License-Identifier: GPL-2.0 > -PLUGINCC := $(CONFIG_PLUGIN_HOSTCC:"%"=%) > GCC_PLUGINS_DIR := $(shell $(CC) -print-file-name=plugin) > > -ifeq ($(PLUGINCC),$(HOSTCC)) > - HOSTLIBS := hostlibs > - HOST_EXTRACFLAGS += -I$(GCC_PLUGINS_DIR)/include -I$(src) -std=gnu99 -ggdb > - export HOST_EXTRACFLAGS > -else > - HOSTLIBS := hostcxxlibs > - HOST_EXTRACXXFLAGS += -I$(GCC_PLUGINS_DIR)/include -I$(src) -std=gnu++98 -fno-rtti > - HOST_EXTRACXXFLAGS += -fno-exceptions -fasynchronous-unwind-tables -ggdb > - HOST_EXTRACXXFLAGS += -Wno-narrowing -Wno-unused-variable -Wno-c++11-compat > - export HOST_EXTRACXXFLAGS > -endif > +HOST_EXTRACXXFLAGS += -I$(GCC_PLUGINS_DIR)/include -I$(src) -std=gnu++98 -fno-rtti > +HOST_EXTRACXXFLAGS += -fno-exceptions -fasynchronous-unwind-tables -ggdb > +HOST_EXTRACXXFLAGS += -Wno-narrowing -Wno-unused-variable -Wno-c++11-compat > > $(obj)/randomize_layout_plugin.o: $(objtree)/$(obj)/randomize_layout_seed.h > quiet_cmd_create_randomize_layout_seed = GENSEED $@ > @@ -22,9 +13,9 @@ $(objtree)/$(obj)/randomize_layout_seed.h: FORCE > $(call if_changed,create_randomize_layout_seed) > targets = randomize_layout_seed.h randomize_layout_hash.h > > -$(HOSTLIBS)-y := $(foreach p,$(GCC_PLUGIN),$(if $(findstring /,$(p)),,$(p))) > -always-y := $($(HOSTLIBS)-y) > +hostcxxlibs-y := $(foreach p,$(GCC_PLUGIN),$(if $(findstring /,$(p)),,$(p))) > +always-y := $(hostcxxlibs-y) > > -$(foreach p,$($(HOSTLIBS)-y:%.so=%),$(eval $(p)-objs := $(p).o)) > +$(foreach p,$(hostcxxlibs-y:%.so=%),$(eval $(p)-objs := $(p).o)) > > clean-files += *.so > -- > 2.17.1 > -- Kees Cook
