Disable gnu-variable-sized-type-not-at-end so that tests and libraries can create overlays of variable sized arrays at the end of structs when using a fixed number of entries, e.g. to get/set a single MSR. It's possible to fudge around the warning, e.g. by defining a custom struct that hardcodes the number of entries, but that is a burden for both developers and readers of the code. lib/x86_64/processor.c:664:19: warning: field 'header' with variable sized type 'struct kvm_msrs' not at the end of a struct or class is a GNU extension [-Wgnu-variable-sized-type-not-at-end] struct kvm_msrs header; ^ lib/x86_64/processor.c:772:19: warning: field 'header' with variable sized type 'struct kvm_msrs' not at the end of a struct or class is a GNU extension [-Wgnu-variable-sized-type-not-at-end] struct kvm_msrs header; ^ lib/x86_64/processor.c:787:19: warning: field 'header' with variable sized type 'struct kvm_msrs' not at the end of a struct or class is a GNU extension [-Wgnu-variable-sized-type-not-at-end] struct kvm_msrs header; ^ 3 warnings generated. x86_64/hyperv_tlb_flush.c:54:18: warning: field 'hv_vp_set' with variable sized type 'struct hv_vpset' not at the end of a struct or class is a GNU extension [-Wgnu-variable-sized-type-not-at-end] struct hv_vpset hv_vp_set; ^ 1 warning generated. x86_64/xen_shinfo_test.c:137:25: warning: field 'info' with variable sized type 'struct kvm_irq_routing' not at the end of a struct or class is a GNU extension [-Wgnu-variable-sized-type-not-at-end] struct kvm_irq_routing info; ^ 1 warning generated. Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx> --- tools/testing/selftests/kvm/Makefile | 1 + 1 file changed, 1 insertion(+) diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile index 2487db21b177..9cff99a1cb2e 100644 --- a/tools/testing/selftests/kvm/Makefile +++ b/tools/testing/selftests/kvm/Makefile @@ -196,6 +196,7 @@ else LINUX_TOOL_ARCH_INCLUDE = $(top_srcdir)/tools/arch/$(ARCH)/include endif CFLAGS += -Wall -Wstrict-prototypes -Wuninitialized -O2 -g -std=gnu99 \ + -Wno-gnu-variable-sized-type-not-at-end \ -fno-builtin-memcmp -fno-builtin-memcpy -fno-builtin-memset \ -fno-stack-protector -fno-PIE -I$(LINUX_TOOL_INCLUDE) \ -I$(LINUX_TOOL_ARCH_INCLUDE) -I$(LINUX_HDR_PATH) -Iinclude \ -- 2.39.0.rc1.256.g54fd8350bd-goog