A previous patch added the --no-wchar-size-warning to the Makefile to avoid this harmless warning: arm-linux-gnueabi-ld: warning: drivers/xen/efi.o uses 2-byte wchar_t yet the output is to use 4-byte wchar_t; use of wchar_t values across objects may fail Changing kbuild to use thin archives instead of recursive linking unfortunately brings the same warning back during the final link. The kernel does not use wchar_t string literals at this point, and xen does not use wchar_t at all (only efi_char16_t), so the flag has no effect, but as pointed out by Jan Beulich, adding a wchar_t string literal would be bad here. Since wchar_t is always defined as u16, independent of the toolchain default, always passing -fshort-wchar is correct and lets us remove the Xen specific hack along with fixing the warning. Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx> Fixes: 971a69db7dc0 ("Xen: don't warn about 2-byte wchar_t in efi") Acked-by: David Vrabel <david.vrabel@xxxxxxxxxx> Link: https://patchwork.kernel.org/patch/9275217/ --- I submitted an earlier patch in August 2016, simply removing the flag in xen, but there seems to be no harm in enabling it globally --- Makefile | 2 +- drivers/xen/Makefile | 3 --- 2 files changed, 1 insertion(+), 4 deletions(-) diff --git a/Makefile b/Makefile index f1533423094f..0fe63a47fd52 100644 --- a/Makefile +++ b/Makefile @@ -396,7 +396,7 @@ LINUXINCLUDE := \ KBUILD_CPPFLAGS := -D__KERNEL__ KBUILD_CFLAGS := -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs \ - -fno-strict-aliasing -fno-common \ + -fno-strict-aliasing -fno-common -fshort-wchar \ -Werror-implicit-function-declaration \ -Wno-format-security \ -std=gnu89 $(call cc-option,-fno-PIE) diff --git a/drivers/xen/Makefile b/drivers/xen/Makefile index 8feab810aed9..7f188b8d0c67 100644 --- a/drivers/xen/Makefile +++ b/drivers/xen/Makefile @@ -7,9 +7,6 @@ obj-y += xenbus/ nostackp := $(call cc-option, -fno-stack-protector) CFLAGS_features.o := $(nostackp) -CFLAGS_efi.o += -fshort-wchar -LDFLAGS += $(call ld-option, --no-wchar-size-warning) - dom0-$(CONFIG_ARM64) += arm-device.o dom0-$(CONFIG_PCI) += pci.o dom0-$(CONFIG_USB_SUPPORT) += dbgp.o -- 2.9.0 -- To unsubscribe from this list: send the line "unsubscribe linux-kbuild" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html