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From: "ian at airs dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug libgcc/106949] Memory leak using VLA with -fsplit-stack
Date: Tue, 04 Oct 2022 00:22:47 +0000	[thread overview]
Message-ID: <bug-106949-4-eULBwtxvB0@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-106949-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106949

--- Comment #3 from Ian Lance Taylor <ian at airs dot com> ---
I don't think your attached patch is going to work.  The code assumes that it
is running within a stack segment.  You can't just add a stack segment without
changing the stack pointer.

But something like your suggestion might work.  If the function is going to
call __morestack_allocate_stack_space, then at the start of the function call a
new function __morestack_allocating_stack_space.  That function can return a
pointer.  The __morestack_allocate_stack_space function can add its allocations
to a list at that pointer.  At the end of the function call another new
function that releases the allocated space.  Some work will be required to make
sure that the space gets released if an exception is thrown.

  parent reply	other threads:[~2022-10-04  0:22 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-09-15  8:18 [Bug libgcc/106949] New: " iam at datacompboy dot ru
2022-09-15  8:21 ` [Bug libgcc/106949] " iam at datacompboy dot ru
2022-10-03 12:25 ` iam at datacompboy dot ru
2022-10-04  0:22 ` ian at airs dot com [this message]
2022-10-04 12:16 ` [Bug libgcc/106949] Memory leak using VLA/alloca " iam at datacompboy dot ru
2022-10-04 15:50 ` iam at datacompboy dot ru

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