kbuild: fix asm-offset generation to work with clang

KBuild abuses the asm statement to write to a file and
clang chokes about these invalid asm statements. Hack it
even more by fooling this is actual valid asm code.

[masahiro:
 Import Jeroen's work for U-Boot:
 http://patchwork.ozlabs.org/patch/375026/
 Tweak sed script a little to avoid garbage '#' for GCC case, like
 #define NR_PAGEFLAGS 23 /* __NR_PAGEFLAGS       # */ ]

Signed-off-by: Jeroen Hofstee <jeroen@myspectrum.nl>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Matthias Kaehlcke <mka@chromium.org>
Tested-by: Matthias Kaehlcke <mka@chromium.org>
This commit is contained in:
Jeroen Hofstee 2017-04-21 15:21:11 +09:00 committed by Masahiro Yamada
parent 7dd47b95b0
commit cf0c3e68aa
2 changed files with 9 additions and 5 deletions

View file

@ -2,14 +2,14 @@
#define __LINUX_KBUILD_H
#define DEFINE(sym, val) \
asm volatile("\n->" #sym " %0 " #val : : "i" (val))
asm volatile("\n.ascii \"->" #sym " %0 " #val "\"" : : "i" (val))
#define BLANK() asm volatile("\n->" : : )
#define BLANK() asm volatile("\n.ascii \"->\"" : : )
#define OFFSET(sym, str, mem) \
DEFINE(sym, offsetof(struct str, mem))
#define COMMENT(x) \
asm volatile("\n->#" x)
asm volatile("\n.ascii \"->#" x "\"")
#endif

View file

@ -413,10 +413,14 @@ cmd_xzmisc = (cat $(filter-out FORCE,$^) | \
# ---------------------------------------------------------------------------
# Default sed regexp - multiline due to syntax constraints
#
# Use [:space:] because LLVM's integrated assembler inserts <tab> around
# the .ascii directive whereas GCC keeps the <space> as-is.
define sed-offsets
"/^->/{s:->#\(.*\):/* \1 */:; \
's:^[[:space:]]*\.ascii[[:space:]]*"\(.*\)".*:\1:; \
/^->/{s:->#\(.*\):/* \1 */:; \
s:^->\([^ ]*\) [\$$#]*\([^ ]*\) \(.*\):#define \1 \2 /* \3 */:; \
s:->::; p;}"
s:->::; p;}'
endef
# Use filechk to avoid rebuilds when a header changes, but the resulting file