https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100262
Bug ID: 100262
Summary: warning on sparc64: 'strcmp' reading 1 or more bytes
from a region of size 0 [-Werror=stringop-overread]
Product: gcc
Version: 11.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c
Assignee: unassigned at gcc dot gnu.org
Reporter: romain.naour at gmail dot com
Target Milestone: ---
Hello,
Using GCC 11.1.0-RC-20210423 for building sparc64 kernel fail to build due to
-Werror=stringop-overread:
arch/sparc/kernel/mdesc.c: In function 'mdesc_node_by_name':
arch/sparc/kernel/mdesc.c:647:22: error: 'strcmp' reading 1 or more bytes from
a region of size 0 [-Werror=stringop-overread]
647 | if (!strcmp(names + ep[ret].name_offset, name))
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
arch/sparc/kernel/mdesc.c:77:33: note: at offset 16 into source object 'mdesc'
of size 16
77 | struct mdesc_hdr mdesc;
| ^~~~~
arch/sparc/kernel/mdesc.c: In function 'mdesc_get_property':
arch/sparc/kernel/mdesc.c:692:22: error: 'strcmp' reading 1 or more bytes from
a region of size 0 [-Werror=stringop-overread]
692 | if (!strcmp(names + ep->name_offset, name)) {
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
arch/sparc/kernel/mdesc.c:77:33: note: at offset 16 into source object 'mdesc'
of size 16
77 | struct mdesc_hdr mdesc;
| ^~~~~
arch/sparc/kernel/mdesc.c: In function 'mdesc_next_arc':
arch/sparc/kernel/mdesc.c:719:21: error: 'strcmp' reading 1 or more bytes from
a region of size 0 [-Werror=stringop-overread]
719 | if (strcmp(names + ep->name_offset, arc_type))
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
arch/sparc/kernel/mdesc.c:77:33: note: at offset 16 into source object 'mdesc'
of size 16
77 | struct mdesc_hdr mdesc;
| ^~~~~
cc1: all warnings being treated as errors
See:
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/tree/arch/sparc/kernel/mdesc.c?h=v5.12#n647
I'm not sure if we need to update the mdesc.c code or disable the warning.
