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 -Werror=implicit-function-declaration 10UAPI_ARCH := $(or $(HEADER_ARCH),$(SRCARCH)) 11 12override c_flags = $(KBUILD_USERCFLAGS) $(UAPI_CFLAGS) -Wp,-MMD,$(depfile) 13 14# The following are excluded for now because they fail to build. 15# 16# Do not add a new header to the blacklist without legitimate reason. 17# Please consider to fix the header first. 18# 19# Sorted alphabetically. 20no-header-test += asm/ucontext.h 21no-header-test += drm/vmwgfx_drm.h 22no-header-test += linux/am437x-vpfe.h 23no-header-test += linux/coda.h 24no-header-test += linux/cyclades.h 25no-header-test += linux/errqueue.h 26no-header-test += linux/hdlc/ioctl.h 27no-header-test += linux/ivtv.h 28no-header-test += linux/matroxfb.h 29no-header-test += linux/omap3isp.h 30no-header-test += linux/omapfb.h 31no-header-test += linux/patchkey.h 32no-header-test += linux/phonet.h 33no-header-test += linux/sctp.h 34no-header-test += linux/sysctl.h 35no-header-test += linux/usb/audio.h 36no-header-test += linux/v4l2-mediabus.h 37no-header-test += linux/v4l2-subdev.h 38no-header-test += linux/videodev2.h 39no-header-test += linux/vm_sockets.h 40no-header-test += sound/asequencer.h 41no-header-test += sound/asoc.h 42no-header-test += sound/asound.h 43no-header-test += sound/compress_offload.h 44no-header-test += sound/emu10k1.h 45no-header-test += sound/sfnt_info.h 46no-header-test += xen/evtchn.h 47no-header-test += xen/gntdev.h 48no-header-test += xen/privcmd.h 49 50# More headers are broken in some architectures 51 52ifneq ($(filter arc openrisc xtensa nios2, $(UAPI_ARCH)),) 53no-header-test += linux/bpf_perf_event.h 54endif 55 56ifeq ($(UAPI_ARCH),sparc) 57no-header-test += asm/uctx.h 58no-header-test += asm/fbio.h 59endif 60 61# asm-generic/*.h is used by asm/*.h, and should not be included directly 62no-header-test += asm-generic/% 63 64# The following are using libc header and types. 65# 66# Do not add a new header to the list without legitimate reason. 67# Please consider to fix the header first. 68# 69# Sorted alphabetically. 70uses-libc += linux/a.out.h 71uses-libc += linux/atmbr2684.h 72uses-libc += linux/auto_dev-ioctl.h 73uses-libc += linux/auto_fs.h 74uses-libc += linux/auto_fs4.h 75uses-libc += linux/btrfs_tree.h 76uses-libc += linux/cec-funcs.h 77uses-libc += linux/cec.h 78uses-libc += linux/dvb/dmx.h 79uses-libc += linux/dvb/video.h 80uses-libc += linux/ethtool.h 81uses-libc += linux/ethtool_netlink.h 82uses-libc += linux/fuse.h 83uses-libc += linux/gsmmux.h 84uses-libc += linux/icmp.h 85uses-libc += linux/idxd.h 86uses-libc += linux/if.h 87uses-libc += linux/if_arp.h 88uses-libc += linux/if_bonding.h 89uses-libc += linux/if_pppox.h 90uses-libc += linux/if_tunnel.h 91uses-libc += linux/input.h 92uses-libc += linux/ip6_tunnel.h 93uses-libc += linux/joystick.h 94uses-libc += linux/llc.h 95uses-libc += linux/mctp.h 96uses-libc += linux/mdio.h 97uses-libc += linux/mii.h 98uses-libc += linux/mptcp.h 99uses-libc += linux/netdevice.h 100uses-libc += linux/netfilter/xt_RATEEST.h 101uses-libc += linux/netfilter/xt_hashlimit.h 102uses-libc += linux/netfilter/xt_physdev.h 103uses-libc += linux/netfilter/xt_rateest.h 104uses-libc += linux/netfilter_arp/arp_tables.h 105uses-libc += linux/netfilter_arp/arpt_mangle.h 106uses-libc += linux/netfilter_bridge.h 107uses-libc += linux/netfilter_bridge/ebtables.h 108uses-libc += linux/netfilter_ipv4.h 109uses-libc += linux/netfilter_ipv4/ip_tables.h 110uses-libc += linux/netfilter_ipv6.h 111uses-libc += linux/netfilter_ipv6/ip6_tables.h 112uses-libc += linux/route.h 113uses-libc += linux/shm.h 114uses-libc += linux/soundcard.h 115uses-libc += linux/string.h 116uses-libc += linux/tipc_config.h 117uses-libc += linux/uhid.h 118uses-libc += linux/uinput.h 119uses-libc += linux/vhost.h 120uses-libc += linux/vhost_types.h 121uses-libc += linux/virtio_ring.h 122uses-libc += linux/wireless.h 123uses-libc += regulator/regulator.h 124uses-libc += scsi/fc/fc_els.h 125 126ifeq ($(UAPI_ARCH),hexagon) 127uses-libc += asm/sigcontext.h 128endif 129 130ifeq ($(UAPI_ARCH),nios2) 131uses-libc += asm/ptrace.h 132endif 133 134ifeq ($(UAPI_ARCH),s390) 135uses-libc += asm/chpid.h 136uses-libc += asm/chsc.h 137endif 138 139always-y := $(patsubst $(obj)/%.h,%.hdrtest, $(shell find $(obj) -name '*.h' 2>/dev/null)) 140 141target-libc = $(filter $(uses-libc), $*.h) 142target-can-compile = $(filter-out $(no-header-test), $*.h) 143 144hdrtest-flags = -fsyntax-only -Werror \ 145 -nostdinc -I $(obj) $(if $(target-libc), -I $(srctree)/usr/dummy-include) 146 147# Include the header twice to detect missing include guard. 148quiet_cmd_hdrtest = HDRTEST $< 149 cmd_hdrtest = \ 150 $(CC) $(c_flags) $(hdrtest-flags) -x c /dev/null \ 151 $(if $(target-can-compile), -include $< -include $<); \ 152 $(PERL) $(src)/headers_check.pl $(obj) $<; \ 153 touch $@ 154 155$(obj)/%.hdrtest: $(obj)/%.h $(src)/headers_check.pl FORCE 156 $(call if_changed_dep,hdrtest) 157 158# Since GNU Make 4.3, $(patsubst $(obj)/%/,%,$(wildcard $(obj)/*/)) works. 159# To support older Make versions, use a somewhat tedious way. 160clean-files += $(filter-out Makefile headers_check.pl, $(notdir $(wildcard $(obj)/*))) 161