gcc 10 with -O2 reports following:
In function ‘strncpy’,
inlined from ‘rpc_sys_packagelist’ at /opt/devel/openwrt/c-projects/rpcd/sys.c:244:4:
/usr/include/x86_64-linux-gnu/bits/string_fortified.h:106:10: error: ‘__builtin_strncpy’ specified bound 128 equals destination size [-Werror=stringop-truncation]
106 | return __builtin___strncpy_chk (__dest, __src, __len, __bos (__dest));
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In function ‘strncpy’,
inlined from ‘rpc_sys_packagelist’ at /opt/devel/openwrt/c-projects/rpcd/sys.c:227:4:
/usr/include/x86_64-linux-gnu/bits/string_fortified.h:106:10: error: ‘__builtin_strncpy’ specified bound 128 equals destination size [-Werror=stringop-truncation]
106 | return __builtin___strncpy_chk (__dest, __src, __len, __bos (__dest));
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Since it is not possible to avoid truncation by strncpy, it is necessary
to make sure the result of strncpy is properly NUL-terminated and the
NUL must be inserted explicitly, after strncpy has returned.
References: #10442
Reported-by: Alexey Smirnov <s.alexey@gmail.com>
Signed-off-by: Petr Štetiar <ynezz@true.cz>
(cherry picked from commit 34ddd2e545)