Package: gdb Version: 6.3-5 Severity: minor Tags: patch
Consider the following gdb session:
----> gdb session <----
$ gdb
GNU gdb 6.3-debian
[...]
(gdb) printf "%lld\n",1
1
(gdb) printf "%yd\n",1
%yd
(gdb) printf "%qd\n",1
/nevyn/local/gdb/gdb-6.3/gdb/utils.c:1013: internal-error: virtual memory exhausted.
A problem internal to GDB has been detected,
further debugging may prove unreliable.
Quit this debugging session? (y or n)
----> end of gdb session <----
The input to this session is precicely the one used to trigger bug #186037. The error message ("virtual memory exhausted"), however, has become different since gdb version 5.3 due to a bug in the function xstrvprintf() at gdb/utils.c:1120 which is unrelated to bug #186037 (in particular, other bugs may be affected as well).
The function xstrvprintf() (gdb/utils.c:1120) looks as follows:
---> snip <---
char *
xstrvprintf (const char *format, va_list ap)
{
char *ret = NULL;
int status = vasprintf (&ret, format, ap);
/* NULL is returned when there was a memory allocation
problem. */
if (ret == NULL)
nomem (0);
/* A negative status (the printed length) with a non-NULL
buffer should never happen, but just to be sure. */
if (status < 0)
internal_error (__FILE__, __LINE__,
"vasprintf call failed (errno %d)", errno);
return ret;
}
---> snap <---According to the libc info file however, the correct way to check if a call to vasprintf failed is to simply check for a negative return value. Furthermore, vasprintf does not seem to set errno. This leads to the wrong error message above.
I therefore propose to remove the ret==NULL check and the reference to errno (see attached patch).
Of course this does not fix #186037, but restores it to its former behaviour.
Regards, Alexander
--- utils.c 2005-02-22 13:28:48.000000000 +0000
+++ utils.c.new 2005-02-22 18:09:53.000000000 +0000
@@ -1120,16 +1120,12 @@
char *
xstrvprintf (const char *format, va_list ap)
{
- char *ret = NULL;
+ char *ret;
int status = vasprintf (&ret, format, ap);
- /* NULL is returned when there was a memory allocation problem. */
- if (ret == NULL)
- nomem (0);
- /* A negative status (the printed length) with a non-NULL buffer
- should never happen, but just to be sure. */
+ /* Negative status indicates error */
if (status < 0)
internal_error (__FILE__, __LINE__,
- "vasprintf call failed (errno %d)", errno);
+ "vasprintf call failed");
return ret;
}
