Hi,

Here is another instance of an alloca that may not be safe.

The value_concat function allocates space on stack to concatenate two
strings (or duplicate a string/char/bool n times). This is not safe
because the requested space could cause alloca to move the stack
pointer beyond stack boundary. Attached patch replaces the alloca with
xmalloc/xfree.

I don't have a test case to demonstrate this, but I think the only
language this can probably be demonstrated in is ADA, a language that
I have never used. I have however verified that this does not cause any
regressions in the testsuite. OK to commit?

Regards,
Siddhesh

gdb/ChangeLog:

	* valarith.c (value_concat): Replace unsafe ALLOCA with
	XMALLOC/XFREE.