From 77342a02ff6e14645916d85c8550dd1011c4f7d7 Mon Sep 17 00:00:00 2001
From: Masahiro Yamada <masahiroy@kernel.org>
Date: Sun, 29 Mar 2020 20:08:32 +0900
Subject: [PATCH] gcc-plugins: drop support for GCC <= 4.7
References: bcs#1181862
Patch-mainline: v5.7-rc1
Git-commit: 77342a02ff6e14645916d85c8550dd1011c4f7d7
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@kernel.org>
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Michal Suchanek <msuchanek@suse.de>
---
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 8074f14d9d0d..c264da2b9b30 100644
--- a/scripts/Kconfig.include
+++ b/scripts/Kconfig.include
@@ -48,9 +48,6 @@ $(error-if,$(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
--- a/scripts/Makefile.build
+++ b/scripts/Makefile.build
@@ -44,7 +44,7 @@ include $(kbuild-file)
include scripts/Makefile.lib
# Do not include host rules unless needed
-ifneq ($(hostprogs-y)$(hostprogs-m)$(hostlibs-y)$(hostlibs-m)$(hostcxxlibs-y)$(hostcxxlibs-m),)
+ifneq ($(hostprogs-y)$(hostprogs-m)$(hostcxxlibs-y)$(hostcxxlibs-m),)
include scripts/Makefile.host
endif
diff --git a/scripts/Makefile.clean b/scripts/Makefile.clean
--- 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) $(targets) $(clean-files) \
$(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
--- a/scripts/Makefile.host
+++ b/scripts/Makefile.host
@@ -22,7 +22,6 @@
# They are linked as C++ code to the executable qconf
__hostprogs := $(sort $(hostprogs-y) $(hostprogs-m))
-host-cshlib := $(sort $(hostlibs-y) $(hostlibs-m))
host-cxxshlib := $(sort $(hostcxxlibs-y) $(hostcxxlibs-m))
# C code
@@ -46,7 +45,6 @@ host-cxxmulti := $(foreach m,$(__hostpro
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))
@@ -54,9 +52,7 @@ host-cmulti := $(addprefix $(obj)/,$(hos
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))
#####
@@ -124,13 +120,6 @@ $(host-cxxobjs): $(obj)/%.o: $(src)/%.cc
$(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.
# This is why a C++ compiler is invoked on a .c file.
@@ -141,15 +130,6 @@ $(host-cxxshobjs): $(obj)/%.o: $(src)/%.
$(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 f8ca236d6165..013ba3a57669 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
--- 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$(src) -std=gnu++98 -fno-rtti
- HOST_EXTRACXXFLAGS += -fno-exceptions -fasynchronous-unwind-tables -ggdb
- HOST_EXTRACXXFLAGS += -Wno-narrowing -Wno-unused-variable
- export HOST_EXTRACXXFLAGS
-endif
+HOST_EXTRACXXFLAGS += -I$(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
$(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.
$(call if_changed,create_randomize_layout_seed)
targets = randomize_layout_seed.h randomize_layout_hash.h
-$(HOSTLIBS)-y := $(foreach p,$(GCC_PLUGIN),$(if $(findstring /,$(p)),,$(p)))
-always := $($(HOSTLIBS)-y)
+hostcxxlibs-y := $(foreach p,$(GCC_PLUGIN),$(if $(findstring /,$(p)),,$(p)))
+always := $(hostcxxlibs-y)
-$(foreach p,$($(HOSTLIBS)-y:%.so=%),$(eval $(p)-objs := $(p).o))
+$(foreach p,$(hostcxxlibs-y:%.so=%),$(eval $(p)-objs := $(p).o))
clean-files += *.so
--
2.26.2