On 12/18/18 11:51 AM, Philippe Mathieu-Daudé wrote:
GCC 8 introduced the -Wstringop-truncation checker to detect truncation by
the strncat and strncpy functions (closely related to -Wstringop-overflow,
which detect buffer overflow by string-modifying functions declared in
<string.h>).
This paragraph talks about a new warning checker, but makes no mention
of an attribute.
Add the QEMU_NONSTRING macro which checks if the compiler supports this
attribute.
Thus, "this attribute" has no antecedent; did you forget to add a
sentence to the previous paragraph, or maybe put the mention of adding
QEMU_NONSTRING after...
From the GCC manual [*]:
The nonstring variable attribute specifies that an object or member
declaration with type array of char, signed char, or unsigned char,
or pointer to such a type is intended to store character arrays that
do not necessarily contain a terminating NUL. This is useful in detecting
uses of such arrays or pointers with functions that expect NUL-terminated
strings, and to avoid warnings when such an array or pointer is used as
an argument to a bounded string manipulation function such as strncpy.
...the explanation of how the attribute was added in tandem with the new
warning checker for silencing specific instances of the warning?
[*]
https://gcc.gnu.org/onlinedocs/gcc/Common-Variable-Attributes.html#index-nonstring-variable-attribute
Suggested-by: Michael S. Tsirkin <[email protected]>
Signed-off-by: Philippe Mathieu-Daudé <[email protected]>
---
include/qemu/compiler.h | 15 +++++++++++++++
1 file changed, 15 insertions(+)
Reviewed-by: Eric Blake <[email protected]>
--
Eric Blake, Principal Software Engineer
Red Hat, Inc. +1-919-301-3266
Virtualization: qemu.org | libvirt.org
