Subject: bug#47715: [PATCH] gzip.c: use a more portable alignment

From: "Dmitry V. Levin" <[email-masked]>
Date: Sun, 11 Apr 2021 20:00:00 +0000

The alignment of 8192 introduced by commit
be0c5581e38332b2ffa8a4cf92076cfde02872b4 is not quite portable:
eu-elflint --gnu-ld complains about the result gzip executable
with the following diagnostics:
section [25] '.bss' not fully contained in segment of program header entry 6

* gzip.c [__alignas_is_defined] (BUFFER_ALIGNED): Decrease alignment
from 8192 back to 4096.
---
 gzip.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/gzip.c b/gzip.c
index 8b8b0bb..0123f82 100644
--- a/gzip.c
+++ b/gzip.c
@@ -132,10 +132,10 @@ static char const *const license_msg[] = {
 /* With IBM_Z_DFLTCC, DEFLATE COMPRESSION works faster with
    page-aligned input and output buffers, and requires page-aligned
    windows; the alignment requirement is 4096.  On other platforms
-   alignment doesn't hurt, and alignment up to 8192 is portable so
+   alignment doesn't hurt, and alignment up to 4096 is portable so
    let's do that.  */
 #ifdef __alignas_is_defined
-# define BUFFER_ALIGNED alignas (8192)
+# define BUFFER_ALIGNED alignas (4096)
 #else
 # define BUFFER_ALIGNED /**/
 #endif
-- 
ldv