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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
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D106949

--- 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 with=
out
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 ca=
ll a
new function __morestack_allocating_stack_space.  That function can return a
pointer.  The __morestack_allocate_stack_space function can add its allocat=
ions
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.=