* Wrong pointer comparison in w32fns.c
@ 2022-10-29 22:36 Juanma Barranquero
2022-10-30 0:57 ` Po Lu
2022-10-30 6:24 ` Eli Zaretskii
0 siblings, 2 replies; 6+ messages in thread
From: Juanma Barranquero @ 2022-10-29 22:36 UTC (permalink / raw)
To: Emacs developers
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Presumably, this is a bug in rarely used code (affecting NT 4 systems):
CC w32fns.o
w32fns.c: In function 'setup_w32_kbdhook':
w32fns.c:2738:24: warning: the comparison will always evaluate as 'true'
for the address of 'newTitle' will never be NULL [-Waddress]
2738 | if (newTitle != NULL)
| ^~
w32fns.c:2733:19: note: 'newTitle' declared here
2733 | wchar_t newTitle[64];
| ^~~~~~~~
requiring something like this:
diff --git i/src/w32fns.c w/src/w32fns.c
index 5f652ae9e4..46c73f762a 100644
--- i/src/w32fns.c
+++ w/src/w32fns.c
@@ -2734,8 +2734,7 @@ setup_w32_kbdhook (void)
int i;
CoCreateGuid (&guid);
- StringFromGUID2 (&guid, newTitle, 64);
- if (newTitle != NULL)
+ if (StringFromGUID2 (&guid, newTitle, 64) && newTitle[0])
{
GetConsoleTitleW (oldTitle, 1024);
SetConsoleTitleW (newTitle);
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^ permalink raw reply related [flat|nested] 6+ messages in thread* Re: Wrong pointer comparison in w32fns.c
2022-10-29 22:36 Wrong pointer comparison in w32fns.c Juanma Barranquero
@ 2022-10-30 0:57 ` Po Lu
2022-10-30 6:47 ` Eli Zaretskii
2022-10-30 6:24 ` Eli Zaretskii
1 sibling, 1 reply; 6+ messages in thread
From: Po Lu @ 2022-10-30 0:57 UTC (permalink / raw)
To: Juanma Barranquero; +Cc: Emacs developers
Juanma Barranquero <lekktu@gmail.com> writes:
> Presumably, this is a bug in rarely used code (affecting NT 4 systems):
>
> CC w32fns.o
> w32fns.c: In function 'setup_w32_kbdhook':
> w32fns.c:2738:24: warning: the comparison will always evaluate as 'true' for the address of 'newTitle' will never be NULL [-Waddress]
> 2738 | if (newTitle != NULL)
> | ^~
> w32fns.c:2733:19: note: 'newTitle' declared here
> 2733 | wchar_t newTitle[64];
> | ^~~~~~~~
>
> requiring something like this:
>
> diff --git i/src/w32fns.c w/src/w32fns.c
> index 5f652ae9e4..46c73f762a 100644
> --- i/src/w32fns.c
> +++ w/src/w32fns.c
> @@ -2734,8 +2734,7 @@ setup_w32_kbdhook (void)
> int i;
>
> CoCreateGuid (&guid);
> - StringFromGUID2 (&guid, newTitle, 64);
> - if (newTitle != NULL)
> + if (StringFromGUID2 (&guid, newTitle, 64) && newTitle[0])
Does this function support Windows 9x?
http://winapi.freetechsecrets.com/ole/OLEStringFromGUID2.htm says
nothing about that.
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: Wrong pointer comparison in w32fns.c
2022-10-29 22:36 Wrong pointer comparison in w32fns.c Juanma Barranquero
2022-10-30 0:57 ` Po Lu
@ 2022-10-30 6:24 ` Eli Zaretskii
2022-10-30 12:13 ` Juanma Barranquero
1 sibling, 1 reply; 6+ messages in thread
From: Eli Zaretskii @ 2022-10-30 6:24 UTC (permalink / raw)
To: Juanma Barranquero; +Cc: emacs-devel
> From: Juanma Barranquero <lekktu@gmail.com>
> Date: Sun, 30 Oct 2022 00:36:20 +0200
>
> Presumably, this is a bug in rarely used code (affecting NT 4 systems):
>
> CC w32fns.o
> w32fns.c: In function 'setup_w32_kbdhook':
> w32fns.c:2738:24: warning: the comparison will always evaluate as 'true' for the address of 'newTitle' will
> never be NULL [-Waddress]
> 2738 | if (newTitle != NULL)
> | ^~
> w32fns.c:2733:19: note: 'newTitle' declared here
> 2733 | wchar_t newTitle[64];
> | ^~~~~~~~
>
Isn't it simply a typo? The intent was to test oldTitle, which is
dynamically allocated by malloc. Right?
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: Wrong pointer comparison in w32fns.c
2022-10-30 6:24 ` Eli Zaretskii
@ 2022-10-30 12:13 ` Juanma Barranquero
2022-10-30 12:47 ` Eli Zaretskii
0 siblings, 1 reply; 6+ messages in thread
From: Juanma Barranquero @ 2022-10-30 12:13 UTC (permalink / raw)
To: Eli Zaretskii; +Cc: emacs-devel
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Ah, possibly.
The output of StringFromGUD2 is then not checked, though perhaps it's
assumed it will always fit in 64 wchar_t..
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^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: Wrong pointer comparison in w32fns.c
2022-10-30 12:13 ` Juanma Barranquero
@ 2022-10-30 12:47 ` Eli Zaretskii
0 siblings, 0 replies; 6+ messages in thread
From: Eli Zaretskii @ 2022-10-30 12:47 UTC (permalink / raw)
To: Juanma Barranquero; +Cc: emacs-devel
> From: Juanma Barranquero <lekktu@gmail.com>
> Date: Sun, 30 Oct 2022 13:13:06 +0100
> Cc: emacs-devel@gnu.org
>
> Ah, possibly.
>
> The output of StringFromGUD2 is then not checked, though perhaps it's assumed it will always fit in 64
> wchar_t..
It should be, since the GUID is a 128-bit number.
Anyway, I've made a change that should take care of both of these
issues.
Thanks.
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2022-10-30 12:47 UTC | newest]
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2022-10-29 22:36 Wrong pointer comparison in w32fns.c Juanma Barranquero
2022-10-30 0:57 ` Po Lu
2022-10-30 6:47 ` Eli Zaretskii
2022-10-30 6:24 ` Eli Zaretskii
2022-10-30 12:13 ` Juanma Barranquero
2022-10-30 12:47 ` Eli Zaretskii
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