| 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. |
| 9 | UAPI_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. |
| 13 | UAPI_CFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS)) |
| 14 | |
| 15 | # USERCFLAGS might contain sysroot location for CC. |
| 16 | UAPI_CFLAGS += $(USERCFLAGS) |
| 17 | |
| 18 | override c_flags = $(UAPI_CFLAGS) -Wp,-MMD,$(depfile) -I $(obj) -I $(srctree)/usr/dummy-include |
| 19 | |
| 20 | # The following are excluded for now because they fail to build. |
| 21 | # |
| 22 | # Do not add a new header to the blacklist without legitimate reason. |
| 23 | # Please consider to fix the header first. |
| 24 | # |
| 25 | # Sorted alphabetically. |
| 26 | no-header-test += asm/ucontext.h |
| 27 | no-header-test += drm/vmwgfx_drm.h |
| 28 | no-header-test += linux/am437x-vpfe.h |
| 29 | no-header-test += linux/coda.h |
| 30 | no-header-test += linux/cyclades.h |
| 31 | no-header-test += linux/errqueue.h |
| 32 | no-header-test += linux/hdlc/ioctl.h |
| 33 | no-header-test += linux/ivtv.h |
| 34 | no-header-test += linux/matroxfb.h |
| 35 | no-header-test += linux/omap3isp.h |
| 36 | no-header-test += linux/omapfb.h |
| 37 | no-header-test += linux/patchkey.h |
| 38 | no-header-test += linux/phonet.h |
| 39 | no-header-test += linux/sctp.h |
| 40 | no-header-test += linux/sysctl.h |
| 41 | no-header-test += linux/usb/audio.h |
| 42 | no-header-test += linux/v4l2-mediabus.h |
| 43 | no-header-test += linux/v4l2-subdev.h |
| 44 | no-header-test += linux/videodev2.h |
| 45 | no-header-test += linux/vm_sockets.h |
| 46 | no-header-test += sound/asequencer.h |
| 47 | no-header-test += sound/asoc.h |
| 48 | no-header-test += sound/asound.h |
| 49 | no-header-test += sound/compress_offload.h |
| 50 | no-header-test += sound/emu10k1.h |
| 51 | no-header-test += sound/sfnt_info.h |
| 52 | no-header-test += xen/evtchn.h |
| 53 | no-header-test += xen/gntdev.h |
| 54 | no-header-test += xen/privcmd.h |
| 55 | |
| 56 | # More headers are broken in some architectures |
| 57 | |
| 58 | ifeq ($(SRCARCH),arc) |
| 59 | no-header-test += linux/bpf_perf_event.h |
| 60 | endif |
| 61 | |
| 62 | ifeq ($(SRCARCH),ia64) |
| 63 | no-header-test += asm/setup.h |
| 64 | no-header-test += asm/sigcontext.h |
| 65 | no-header-test += linux/if_bonding.h |
| 66 | endif |
| 67 | |
| 68 | ifeq ($(SRCARCH),powerpc) |
| 69 | no-header-test += linux/bpf_perf_event.h |
| 70 | endif |
| 71 | |
| 72 | ifeq ($(SRCARCH),sparc) |
| 73 | no-header-test += asm/uctx.h |
| 74 | no-header-test += asm/fbio.h |
| 75 | endif |
| 76 | |
| 77 | # asm-generic/*.h is used by asm/*.h, and should not be included directly |
| 78 | no-header-test += asm-generic/% |
| 79 | |
| 80 | always-y := $(patsubst $(obj)/%.h,%.hdrtest, $(shell find $(obj) -name '*.h' 2>/dev/null)) |
| 81 | |
| 82 | # Include the header twice to detect missing include guard. |
| 83 | quiet_cmd_hdrtest = HDRTEST $< |
| 84 | cmd_hdrtest = \ |
| 85 | $(CC) $(c_flags) -fsyntax-only -x c /dev/null \ |
| 86 | $(if $(filter-out $(no-header-test), $*.h), -include $< -include $<); \ |
| 87 | $(PERL) $(srctree)/$(src)/headers_check.pl $(obj) $(SRCARCH) $<; \ |
| 88 | touch $@ |
| 89 | |
| 90 | $(obj)/%.hdrtest: $(obj)/%.h FORCE |
| 91 | $(call if_changed_dep,hdrtest) |
| 92 | |
| 93 | # Since GNU Make 4.3, $(patsubst $(obj)/%/,%,$(wildcard $(obj)/*/)) works. |
| 94 | # To support older Make versions, use a somewhat tedious way. |
| 95 | clean-files += $(filter-out Makefile headers_check.pl, $(notdir $(wildcard $(obj)/*))) |