[PATCH v2] scripts: headers_install.sh: Normalize __ASSEMBLY__ to __ASSEMBLER__

[PATCH v2] scripts: headers_install.sh: Normalize __ASSEMBLY__ to __ASSEMBLER__

[Thomas Huth]

From: Thomas Huth <thuth@redhat.com>

A previous patch to headers_install.sh normalized the usage of
__ASSEMBLER__ to __ASSEMBLY__ in the UAPI headers due to two reasons:

1) There was the concern that the UAPI headers might be used with
non-GCC-compatible compilers, which do not define __ASSEMBLER__
automatically.

But other C compilers like PCC (see
https://github.com/IanHarvey/pcc/blob/cvs2git/2018.09.20/cc/cc/cc.1#L405)
and Tiny-C (see https://repo.or.cz/tinycc.git/commitdiff/a25325e9be13e52a),
are defining __ASSEMBLER__ for compiling assembler files, too, so using
it in UAPI header files should really be fine.

2) During the migration phase, the UAPI headers will use a mix of *both*
__ASSEMBLY__ and __ASSEMBLER__ at the same time, which is ugly and
inconsistent.

That's true. But since we already shipped a couple of kernel versions
that used __ASSEMBLER__ in the UAPI headers for certain architectures,
we might now break user space programs that have been developed with
these kernel versions if we switch back to __ASSEMBLY__.

Thus let's better always use the macro that is defined by the compilers
and standardize on __ASSEMBLER__ instead of __ASSEMBLY__ in all of the
UAPI header files now.

Suggested-by: Thomas Weißschuh <linux@weissschuh.net>
Link: https://lore.kernel.org/all/2030a963-33bc-43fe-9a2b-9c626d7d8360@redhat.com/
Reviewed-by: Nicolas Schier <n.schier@fritz.com>
Tested-by: Nicolas Schier <n.schier@fritz.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
---
 v2: Updated patch description

 scripts/headers_install.sh | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/scripts/headers_install.sh b/scripts/headers_install.sh
index 83e4475968781..2f1d1767ca267 100755
--- a/scripts/headers_install.sh
+++ b/scripts/headers_install.sh
@@ -36,7 +36,7 @@ sed -E -e '
 	s/(^|[^a-zA-Z0-9])__packed([^a-zA-Z0-9_]|$)/\1__attribute__((packed))\2/g
 	s/(^|[[:space:](])(inline|asm|volatile)([[:space:](]|$)/\1__\2__\3/g
 	s@#(ifndef|define|endif[[:space:]]*/[*])[[:space:]]*_UAPI@#\1 @
-	s/__ASSEMBLER__/__ASSEMBLY__/g
+	s/__ASSEMBLY__/__ASSEMBLER__/g
 ' $INFILE > $TMPFILE || exit 1
 
 scripts/unifdef -U__KERNEL__ -D__EXPORTED_HEADERS__ $TMPFILE > $OUTFILE
-- 
2.55.0