1# SPDX-License-Identifier: GPL-2.0-only
2
3# cc-cross-prefix
4# Usage: CROSS_COMPILE := $(call cc-cross-prefix, m68k-linux-gnu- m68k-linux-)
5# Return first <prefix> where a <prefix>gcc is found in PATH.
6# If no gcc found in PATH with listed prefixes return nothing
7#
8# Note: '2>/dev/null' is here to force Make to invoke a shell. Otherwise, it
9# would try to directly execute the shell builtin 'command'. This workaround
10# should be kept for a long time since this issue was fixed only after the
11# GNU Make 4.2.1 release.
12cc-cross-prefix = $(firstword $(foreach c, $(1), \
13			$(if $(shell command -v -- $(c)gcc 2>/dev/null), $(c))))
14
15# output directory for tests below
16TMPOUT = $(if $(KBUILD_EXTMOD),$(firstword $(KBUILD_EXTMOD))/).tmp_$$$$
17
18# try-run
19# Usage: option = $(call try-run, $(CC)...-o "$$TMP",option-ok,otherwise)
20# Exit code chooses option. "$$TMP" serves as a temporary file and is
21# automatically cleaned up.
22try-run = $(shell set -e;		\
23	TMP=$(TMPOUT)/tmp;		\
24	trap "rm -rf $(TMPOUT)" EXIT;	\
25	mkdir -p $(TMPOUT);		\
26	if ($(1)) >/dev/null 2>&1;	\
27	then echo "$(2)";		\
28	else echo "$(3)";		\
29	fi)
30
31# as-option
32# Usage: cflags-y += $(call as-option,-Wa$(comma)-isa=foo,)
33
34as-option = $(call try-run,\
35	$(CC) $(KBUILD_CFLAGS) $(1) -c -x assembler /dev/null -o "$$TMP",$(1),$(2))
36
37# as-instr
38# Usage: cflags-y += $(call as-instr,instr,option1,option2)
39
40as-instr = $(call try-run,\
41	printf "%b\n" "$(1)" | $(CC) $(KBUILD_AFLAGS) -c -x assembler -o "$$TMP" -,$(2),$(3))
42
43# __cc-option
44# Usage: MY_CFLAGS += $(call __cc-option,$(CC),$(MY_CFLAGS),-march=winchip-c6,-march=i586)
45__cc-option = $(call try-run,\
46	$(1) -Werror $(2) $(3) -c -x c /dev/null -o "$$TMP",$(3),$(4))
47
48# cc-option
49# Usage: cflags-y += $(call cc-option,-march=winchip-c6,-march=i586)
50
51cc-option = $(call __cc-option, $(CC),\
52	$(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS),$(1),$(2))
53
54# cc-option-yn
55# Usage: flag := $(call cc-option-yn,-march=winchip-c6)
56cc-option-yn = $(call try-run,\
57	$(CC) -Werror $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(1) -c -x c /dev/null -o "$$TMP",y,n)
58
59# cc-disable-warning
60# Usage: cflags-y += $(call cc-disable-warning,unused-but-set-variable)
61cc-disable-warning = $(call try-run,\
62	$(CC) -Werror $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) -W$(strip $(1)) -c -x c /dev/null -o "$$TMP",-Wno-$(strip $(1)))
63
64# gcc-min-version
65# Usage: cflags-$(call gcc-min-version, 70100) += -foo
66gcc-min-version = $(shell [ $(CONFIG_GCC_VERSION)0 -ge $(1)0 ] && echo y)
67
68# clang-min-version
69# Usage: cflags-$(call clang-min-version, 110000) += -foo
70clang-min-version = $(shell [ $(CONFIG_CLANG_VERSION)0 -ge $(1)0 ] && echo y)
71
72# ld-option
73# Usage: KBUILD_LDFLAGS += $(call ld-option, -X, -Y)
74ld-option = $(call try-run, $(LD) $(KBUILD_LDFLAGS) $(1) -v,$(1),$(2),$(3))
75
76# ld-ifversion
77# Usage:  $(call ld-ifversion, -ge, 22252, y)
78ld-ifversion = $(shell [ $(CONFIG_LD_VERSION)0 $(1) $(2)0 ] && echo $(3) || echo $(4))
79