lib: Revert use of fallthrough pseudo-keyword in lib/

The following build error for powerpc64 was reported by Nathan Chancellor:

  "$ scripts/config --file arch/powerpc/configs/powernv_defconfig -e KERNEL_XZ

   $ make -skj"$(nproc)" ARCH=powerpc CROSS_COMPILE=powerpc64le-linux- distclean powernv_defconfig zImage
   ...
   In file included from arch/powerpc/boot/../../../lib/decompress_unxz.c:234,
                    from arch/powerpc/boot/decompress.c:38:
   arch/powerpc/boot/../../../lib/xz/xz_dec_stream.c: In function 'dec_main':
   arch/powerpc/boot/../../../lib/xz/xz_dec_stream.c:586:4: error: 'fallthrough' undeclared (first use in this function)
     586 |    fallthrough;
         |    ^~~~~~~~~~~

   This will end up affecting distribution configurations such as Debian
   and OpenSUSE according to my testing. I am not sure what the solution
   is, the PowerPC wrapper does not set -D__KERNEL__ so I am not sure
   that compiler_attributes.h can be safely included."

In order to avoid these sort of problems, it seems that the best
solution is to use /* fall through */ comments instead of the
fallthrough pseudo-keyword macro in lib/, for now.

Reported-by: Nathan Chancellor <natechancellor@gmail.com>
Fixes: df561f6688 ("treewide: Use fallthrough pseudo-keyword")
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Reviewed-and-tested-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Gustavo A. R. Silva
2020-08-24 15:36:14 -05:00
committed by Linus Torvalds
parent 9907ab3714
commit 6a9dc5fd61
16 changed files with 64 additions and 64 deletions

View File

@@ -1043,7 +1043,7 @@ XZ_EXTERN enum xz_ret xz_dec_lzma2_run(struct xz_dec_lzma2 *s,
s->lzma2.sequence = SEQ_LZMA_PREPARE;
fallthrough;
/* fall through */
case SEQ_LZMA_PREPARE:
if (s->lzma2.compressed < RC_INIT_BYTES)
@@ -1055,7 +1055,7 @@ XZ_EXTERN enum xz_ret xz_dec_lzma2_run(struct xz_dec_lzma2 *s,
s->lzma2.compressed -= RC_INIT_BYTES;
s->lzma2.sequence = SEQ_LZMA_RUN;
fallthrough;
/* fall through */
case SEQ_LZMA_RUN:
/*

View File

@@ -583,7 +583,7 @@ static enum xz_ret dec_main(struct xz_dec *s, struct xz_buf *b)
if (ret != XZ_OK)
return ret;
fallthrough;
/* fall through */
case SEQ_BLOCK_START:
/* We need one byte of input to continue. */
@@ -608,7 +608,7 @@ static enum xz_ret dec_main(struct xz_dec *s, struct xz_buf *b)
s->temp.pos = 0;
s->sequence = SEQ_BLOCK_HEADER;
fallthrough;
/* fall through */
case SEQ_BLOCK_HEADER:
if (!fill_temp(s, b))
@@ -620,7 +620,7 @@ static enum xz_ret dec_main(struct xz_dec *s, struct xz_buf *b)
s->sequence = SEQ_BLOCK_UNCOMPRESS;
fallthrough;
/* fall through */
case SEQ_BLOCK_UNCOMPRESS:
ret = dec_block(s, b);
@@ -629,7 +629,7 @@ static enum xz_ret dec_main(struct xz_dec *s, struct xz_buf *b)
s->sequence = SEQ_BLOCK_PADDING;
fallthrough;
/* fall through */
case SEQ_BLOCK_PADDING:
/*
@@ -651,7 +651,7 @@ static enum xz_ret dec_main(struct xz_dec *s, struct xz_buf *b)
s->sequence = SEQ_BLOCK_CHECK;
fallthrough;
/* fall through */
case SEQ_BLOCK_CHECK:
if (s->check_type == XZ_CHECK_CRC32) {
@@ -675,7 +675,7 @@ static enum xz_ret dec_main(struct xz_dec *s, struct xz_buf *b)
s->sequence = SEQ_INDEX_PADDING;
fallthrough;
/* fall through */
case SEQ_INDEX_PADDING:
while ((s->index.size + (b->in_pos - s->in_start))
@@ -699,7 +699,7 @@ static enum xz_ret dec_main(struct xz_dec *s, struct xz_buf *b)
s->sequence = SEQ_INDEX_CRC32;
fallthrough;
/* fall through */
case SEQ_INDEX_CRC32:
ret = crc32_validate(s, b);
@@ -709,7 +709,7 @@ static enum xz_ret dec_main(struct xz_dec *s, struct xz_buf *b)
s->temp.size = STREAM_HEADER_SIZE;
s->sequence = SEQ_STREAM_FOOTER;
fallthrough;
/* fall through */
case SEQ_STREAM_FOOTER:
if (!fill_temp(s, b))