From: Julien Grall <jgr...@amazon.com> Right now, all tools and hypervisor will be complied with the option -Wdeclaration-after-statement. While most of the code in the hypervisor is controlled by us, for tools we may import external libraries.
The build will fail if one of them are using the construct we are trying to prevent. This is the case when building against Python 3.12 and Yocto: | In file included from /srv/storage/alex/yocto/build-virt/tmp/work/core2-64-poky-linux/xen-tools/4.17+stable/recipe-sysroot/usr/include/python3.12/Python.h:44, | from xen/lowlevel/xc/xc.c:8: | /srv/storage/alex/yocto/build-virt/tmp/work/core2-64-poky-linux/xen-tools/4.17+stable/recipe-sysroot/usr/include/python3.12/object.h: In function 'Py_SIZE': | /srv/storage/alex/yocto/build-virt/tmp/work/core2-64-poky-linux/xen-tools/4.17+stable/recipe-sysroot/usr/include/python3.12/object.h:233:5: error: ISO C90 forbids mixed declarations and code [-Werror=declaration-after-statement] | 233 | PyVarObject *var_ob = _PyVarObject_CAST(ob); | | ^~~~~~~~~~~ | In file included from /srv/storage/alex/yocto/build-virt/tmp/work/core2-64-poky-linux/xen-tools/4.17+stable/recipe-sysroot/usr/include/python3.12/Python.h:53: | /srv/storage/alex/yocto/build-virt/tmp/work/core2-64-poky-linux/xen-tools/4.17+stable/recipe-sysroot/usr/include/python3.12/cpython/longintrepr.h: In function '_PyLong_CompactValue': | /srv/storage/alex/yocto/build-virt/tmp/work/core2-64-poky-linux/xen-tools/4.17+stable/recipe-sysroot/usr/include/python3.12/cpython/longintrepr.h:121:5: error: ISO C90 forbids mixed declarations and code [-Werror=declaration-after-statement] | 121 | Py_ssize_t sign = 1 - (op->long_value.lv_tag & _PyLong_SIGN_MASK); | | ^~~~~~~~~~ | cc1: all warnings being treated as errors Looking at the tools directory, a fair few directory already add -Wno-declaration-after-statement to inhibit the default behavior. We have always build the hypervisor with the flag, so for now remove only the flag for anything but the hypervisor. We can decide at later time whether we want to relax. Also remove the -Wno-declaration-after-statement in some subdirectory as the flag is now unnecessary. Part of the commit message was take from Alexander's first proposal: Link: https://lore.kernel.org/xen-devel/20231128174729.3880113-1-a...@linutronix.de/ Reported-by: Alexander Kanavin <a...@linutronix.de> Signed-off-by: Julien Grall <jgr...@amazon.com> --- I think the decision to remove the flag for the hypervisor is a separate discussion. Personally I am on the fence. We could also re-enable the flags to some of the tools directory if wanted. I chose the most convenience approach for now. --- Config.mk | 2 -- stubdom/Makefile | 2 +- stubdom/vtpmmgr/Makefile | 2 +- tools/libs/light/Makefile | 3 +-- tools/libs/util/Makefile | 3 +-- tools/tests/depriv/Makefile | 2 -- tools/xl/Makefile | 3 +-- xen/Makefile | 1 + 8 files changed, 6 insertions(+), 12 deletions(-) diff --git a/Config.mk b/Config.mk index 2c43702958eb..7e67b91de293 100644 --- a/Config.mk +++ b/Config.mk @@ -177,8 +177,6 @@ CFLAGS += -std=gnu99 CFLAGS += -Wall -Wstrict-prototypes -$(call cc-option-add,HOSTCFLAGS,HOSTCC,-Wdeclaration-after-statement) -$(call cc-option-add,CFLAGS,CC,-Wdeclaration-after-statement) $(call cc-option-add,CFLAGS,CC,-Wno-unused-but-set-variable) $(call cc-option-add,CFLAGS,CC,-Wno-unused-local-typedefs) diff --git a/stubdom/Makefile b/stubdom/Makefile index 71c9b2200e68..8c503c2bf8de 100644 --- a/stubdom/Makefile +++ b/stubdom/Makefile @@ -245,7 +245,7 @@ tpm_emulator-$(XEN_TARGET_ARCH): tpm_emulator-$(TPMEMU_VERSION).tar.gz patch -d $@ -p1 < vtpm-command-duration.patch patch -d $@ -p1 < vtpm-tpm_bn_t-addr.patch mkdir $@/build - cd $@/build; CC=${CC} $(CMAKE) .. -DCMAKE_C_FLAGS:STRING="-std=c99 -DTPM_NO_EXTERN $(TARGET_CPPFLAGS) $(TARGET_CFLAGS) -Wno-declaration-after-statement" + cd $@/build; CC=${CC} $(CMAKE) .. -DCMAKE_C_FLAGS:STRING="-std=c99 -DTPM_NO_EXTERN $(TARGET_CPPFLAGS) $(TARGET_CFLAGS)" touch $@ TPMEMU_STAMPFILE=$(CROSS_ROOT)/$(GNU_TARGET_ARCH)-xen-elf/lib/libtpm.a diff --git a/stubdom/vtpmmgr/Makefile b/stubdom/vtpmmgr/Makefile index 6dae034a0778..c29bb498381c 100644 --- a/stubdom/vtpmmgr/Makefile +++ b/stubdom/vtpmmgr/Makefile @@ -17,7 +17,7 @@ OBJS += vtpm_disk.o disk_tpm.o disk_io.o disk_crypto.o disk_read.o disk_write.o OBJS += mgmt_authority.o CFLAGS+=-Werror -Iutil -Icrypto -Itcs -CFLAGS+=-Wno-declaration-after-statement -Wno-unused-label +CFLAGS+=-Wno-unused-label build: $(TARGET) $(TARGET): $(OBJS) diff --git a/tools/libs/light/Makefile b/tools/libs/light/Makefile index ba4c1b79336f..37e4d1670986 100644 --- a/tools/libs/light/Makefile +++ b/tools/libs/light/Makefile @@ -38,8 +38,7 @@ vpath static_tables.c $(ACPI_PATH)/ OBJS-$(CONFIG_X86) += $(ACPI_OBJS) -CFLAGS += -Wno-format-zero-length -Wmissing-declarations \ - -Wno-declaration-after-statement -Wformat-nonliteral +CFLAGS += -Wno-format-zero-length -Wmissing-declarations -Wformat-nonliteral CFLAGS-$(CONFIG_X86) += -DCONFIG_PCI_SUPP_LEGACY_IRQ diff --git a/tools/libs/util/Makefile b/tools/libs/util/Makefile index c3b21875dcd8..936ec90a3153 100644 --- a/tools/libs/util/Makefile +++ b/tools/libs/util/Makefile @@ -9,8 +9,7 @@ OBJS-y += libxlu_disk.o OBJS-y += libxlu_vif.o OBJS-y += libxlu_pci.o -CFLAGS += -Wno-format-zero-length -Wmissing-declarations \ - -Wno-declaration-after-statement -Wformat-nonliteral +CFLAGS += -Wno-format-zero-length -Wmissing-declarations -Wformat-nonliteral CFLAGS += $(CFLAGS_libxenctrl) CFLAGS += $(PTHREAD_CFLAGS) diff --git a/tools/tests/depriv/Makefile b/tools/tests/depriv/Makefile index 7d9e3b01bbd4..5404a12f4780 100644 --- a/tools/tests/depriv/Makefile +++ b/tools/tests/depriv/Makefile @@ -1,8 +1,6 @@ XEN_ROOT=$(CURDIR)/../../.. include $(XEN_ROOT)/tools/Rules.mk -CFLAGS += -Wno-declaration-after-statement - CFLAGS += $(CFLAGS_xeninclude) CFLAGS += $(CFLAGS_libxenctrl) CFLAGS += $(CFLAGS_libxencall) diff --git a/tools/xl/Makefile b/tools/xl/Makefile index 5f7aa5f46c87..d742e96a5b3e 100644 --- a/tools/xl/Makefile +++ b/tools/xl/Makefile @@ -5,8 +5,7 @@ XEN_ROOT = $(CURDIR)/../.. include $(XEN_ROOT)/tools/Rules.mk -CFLAGS += -Wno-format-zero-length -Wmissing-declarations \ - -Wno-declaration-after-statement -Wformat-nonliteral +CFLAGS += -Wno-format-zero-length -Wmissing-declarations -Wformat-nonliteral CFLAGS += -fPIC CFLAGS += $(PTHREAD_CFLAGS) diff --git a/xen/Makefile b/xen/Makefile index ca571103c868..360fb6dcae57 100644 --- a/xen/Makefile +++ b/xen/Makefile @@ -393,6 +393,7 @@ CFLAGS-$(CONFIG_CC_SPLIT_SECTIONS) += -ffunction-sections -fdata-sections CFLAGS += -nostdinc -fno-builtin -fno-common CFLAGS += -Werror -Wredundant-decls -Wwrite-strings -Wno-pointer-arith +$(call cc-option-add,CFLAGS,CC,-Wdeclaration-after-statement) $(call cc-option-add,CFLAGS,CC,-Wvla) CFLAGS += -pipe -D__XEN__ -include $(srctree)/include/xen/config.h CFLAGS-$(CONFIG_DEBUG_INFO) += -g -- 2.40.1
