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Re: Relax restriction slightly on integral mode structs


Richard Kenner wrote:
We can allow non-BLKmode RECORD_TYPEs even if a field crosses a word
boundary if that field is larger than a word since we have code to handle
that case.

This looks like a potential silent ABI change.


The default function argument/return macros check for BLKmode objects and handle them specially. The result is that if you change the rule that decides whether a structure is BLKmode or not, then you are most likely changing the ABI for at least one target.

Of course, the function argument/return macros are broken, since they should be checking types instead of modes, but we are stuck with them for now. Thus we need to be careful about making gratuitous changes to the code that decides whether a structure is BLKmode or not.

Jim


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