kbuild: uapi: use custom stub headers instead of libc ones

Now that custom stub headers are provided for all libc headers used from
the UAPI headers, the dependency on the toolchain libc can be dropped.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Nicolas Schier <nsc@kernel.org>
Tested-by: Nicolas Schier <nsc@kernel.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://patch.msgid.link/20260227-kbuild-uapi-libc-v1-7-c17de0d19776@weissschuh.net
Signed-off-by: Nicolas Schier <nsc@kernel.org>

diff --git a/usr/include/Makefile b/usr/include/Makefile
index fdc79cffcc9774f36bac204508237d284d320f3f..d352280b0e4a35c4271ccbcbe76599190be8f5bb 100644 (file)
--- a/usr/include/Makefile
+++ b/usr/include/Makefile
@@ -138,14 +138,13 @@ endif
 always-y := $(patsubst $(obj)/%.h,%.hdrtest, $(shell find $(obj) -name '*.h' 2>/dev/null))
 
 target-no-libc = $(filter-out $(uses-libc), $*.h)
-target-can-compile = $(and $(filter-out $(no-header-test), $*.h), \
-                           $(or $(CONFIG_CC_CAN_LINK), $(target-no-libc)))
+target-can-compile = $(filter-out $(no-header-test), $*.h)
 
 # Include the header twice to detect missing include guard.
 quiet_cmd_hdrtest = HDRTEST $<
       cmd_hdrtest = \
                $(CC) $(c_flags) -fsyntax-only -Werror -x c /dev/null \
-                       $(if $(target-no-libc), -nostdinc, -I $(srctree)/usr/dummy-include) \
+                       -nostdinc $(if $(target-no-libc), , -I $(srctree)/usr/dummy-include) \
                        $(if $(target-can-compile), -include $< -include $<); \
                $(PERL) $(src)/headers_check.pl $(obj) $<; \
                touch $@