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Re: [PATCH] Added information about inline assembler in stack calculations (.su files)


On 11/26/18 7:02 AM, Torbjorn SVENSSON wrote:
> Hi,
> 
> Attached is a small patch that, in case of inline assembler code, 
> indicates that the function stack usage is uncertain due to inline 
> assembler.
> 
> The test suite are using "nop" as an assembler instruction on all 
> targets, is this acceptable or is there a better way to test this?
> 
> Patch has been tested on gcc-arm-none-eabi-7-2018-q2-update for both 
> arm-none-eabi and x86_64-linux-gnu and SVN head (r266454) for 
> x86_64-linux-gnu.
One could argue that allocating stack space inside an ASM is a really
bad idea.  Consider things like dwarf debugging and unwind tables.  If
you're allocating stack inside an ASM that stuff is going to be totally
wrong.

So I think my question before moving forward with something like this is
whether or not it makes sense at all to bother dumping data for a
scenario that we'd probably suggest developers avoid to begin with.

jeff


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