1# SPDX-License-Identifier: GPL-2.0-only 2 3# Unlike the kernel space, exported headers are written in standard C. 4# - Forbid C++ style comments 5# - Use '__inline__', '__asm__' instead of 'inline', 'asm' 6# 7# -std=c90 (equivalent to -ansi) catches the violation of those. 8# We cannot go as far as adding -Wpedantic since it emits too many warnings. 9UAPI_CFLAGS := -std=c90 -Wall -Werror=implicit-function-declaration 10 11# In theory, we do not care -m32 or -m64 for header compile tests. 12# It is here just because CONFIG_CC_CAN_LINK is tested with -m32 or -m64. 13UAPI_CFLAGS += $(filter -m32 -m64, $(KBUILD_CFLAGS)) 14 15override c_flags = $(UAPI_CFLAGS) -Wp,-MMD,$(depfile) -I$(objtree)/usr/include 16 17# The following are excluded for now because they fail to build. 18# 19# Do not add a new header to the blacklist without legitimate reason. 20# Please consider to fix the header first. 21# 22# Sorted alphabetically. 23no-header-test += asm/shmbuf.h 24no-header-test += asm/signal.h 25no-header-test += asm/ucontext.h 26no-header-test += drm/vmwgfx_drm.h 27no-header-test += linux/am437x-vpfe.h 28no-header-test += linux/android/binder.h 29no-header-test += linux/android/binderfs.h 30no-header-test += linux/coda.h 31no-header-test += linux/errqueue.h 32no-header-test += linux/fsmap.h 33no-header-test += linux/hdlc/ioctl.h 34no-header-test += linux/ivtv.h 35no-header-test += linux/kexec.h 36no-header-test += linux/matroxfb.h 37no-header-test += linux/omap3isp.h 38no-header-test += linux/omapfb.h 39no-header-test += linux/patchkey.h 40no-header-test += linux/phonet.h 41no-header-test += linux/reiserfs_xattr.h 42no-header-test += linux/sctp.h 43no-header-test += linux/signal.h 44no-header-test += linux/sysctl.h 45no-header-test += linux/usb/audio.h 46no-header-test += linux/v4l2-mediabus.h 47no-header-test += linux/v4l2-subdev.h 48no-header-test += linux/videodev2.h 49no-header-test += linux/vm_sockets.h 50no-header-test += sound/asequencer.h 51no-header-test += sound/asoc.h 52no-header-test += sound/asound.h 53no-header-test += sound/compress_offload.h 54no-header-test += sound/emu10k1.h 55no-header-test += sound/sfnt_info.h 56no-header-test += xen/evtchn.h 57no-header-test += xen/gntdev.h 58no-header-test += xen/privcmd.h 59 60# More headers are broken in some architectures 61 62ifeq ($(SRCARCH),arc) 63no-header-test += linux/bpf_perf_event.h 64endif 65 66ifeq ($(SRCARCH),ia64) 67no-header-test += asm/setup.h 68no-header-test += asm/sigcontext.h 69no-header-test += linux/if_bonding.h 70endif 71 72ifeq ($(SRCARCH),mips) 73no-header-test += asm/stat.h 74endif 75 76ifeq ($(SRCARCH),powerpc) 77no-header-test += asm/stat.h 78no-header-test += linux/bpf_perf_event.h 79endif 80 81ifeq ($(SRCARCH),riscv) 82no-header-test += linux/bpf_perf_event.h 83endif 84 85ifeq ($(SRCARCH),sparc) 86no-header-test += asm/stat.h 87no-header-test += asm/uctx.h 88no-header-test += asm/fbio.h 89endif 90 91# asm-generic/*.h is used by asm/*.h, and should not be included directly 92no-header-test += asm-generic/% 93 94extra-y := $(patsubst $(obj)/%.h,%.hdrtest, $(shell find $(obj) -name '*.h' 2>/dev/null)) 95 96# Include the header twice to detect missing include guard. 97quiet_cmd_hdrtest = HDRTEST $< 98 cmd_hdrtest = \ 99 $(CC) $(c_flags) -S -o /dev/null -x c /dev/null \ 100 $(if $(filter-out $(no-header-test), $*.h), -include $< -include $<); \ 101 $(PERL) $(srctree)/$(src)/headers_check.pl $(obj) $(SRCARCH) $<; \ 102 touch $@ 103 104$(obj)/%.hdrtest: $(obj)/%.h FORCE 105 $(call if_changed_dep,hdrtest) 106 107# Since GNU Make 4.3, $(patsubst $(obj)/%/,%,$(wildcard $(obj)/*/)) works. 108# To support older Make versions, use a somewhat tedious way. 109clean-files += $(filter-out Makefile headers_check.pl, $(notdir $(wildcard $(obj)/*))) 110