[PATCH] D62731: [RFC] Add support for options -frounding-math, -fp-model=, and -fp-exception-behavior=, : Specify floating point behavior

[John McCall via Phabricator via llvm-commits]

rjmccall added inline comments.


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Comment at: clang/docs/UsersManual.rst:1330
+   and ``fast``.
+   Details:
+
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rjmccall wrote:
> "provided by other, single-purpose floating point options."
I don't know why you keep including "clang" as a modifier here; this is the clang documentation, and all of these options are clang options no matter where they might have been borrowed from.


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Comment at: clang/docs/UsersManual.rst:1341
+   has been selected, then the compiler will issue a diagnostic warning
+   that the override has occurred.
+
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mibintc wrote:
> rjmccall wrote:
> > That's not typical driver behavior; why this choice?
> The rationale for the warnings is that the floating point options are sufficiently complicated that it makes sense to warn the uses that one of the later options supplied on the command line is undoing a choice made earlier.  It's not obvious that e.g. the setting for fassociative-math is also controlled by  -fp-model=strict
Okay.  Well, it's a new option, so new behavior is alright, but if you're worried about the collisions having arbitrary effects that you'll have to maintain compatibility with, you should consider making it an error instead, because a warning still means it's permitted.


Repository:
  rL LLVM

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  https://reviews.llvm.org/D62731/new/

https://reviews.llvm.org/D62731