Re: [PATCH v1 0/4] [RFC] Implement Trampoline File Descriptor

From: Madhavan T. Venkataraman
Date: Tue Aug 04 2020 - 10:48:17 EST

On 8/4/20 9:33 AM, David Laight wrote:
>>> If you look at the libffi reference patch I have included, the architecture
>>> specific changes to use trampfd just involve a single C function call to
>>> a common code function.
> No idea what libffi is, but it must surely be simpler to
> rewrite it to avoid nested function definitions.

Sorry if I wasn't clear.

libffi is a separate use case and GCC nested functions is a separate one.
libffi is not used to solve the nested function stuff.

For nested functions, GCC generates trampoline code and arranges to
place it on the stack and execute it.

I agree with your other points about nested function implementation.

> Or find a book from the 1960s on how to do recursive
> calls and nested functions in FORTRAN-IV.
> David
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