aaron.ballman added inline comments.
================
Comment at: clang/lib/Frontend/FrontendAction.cpp:845-855
+ if (Input.isFile() && Input.getFile() == "-") {
+ Preprocessor &PP = CI.getPreprocessor();
+ std::string PredefineBuffer;
+ PredefineBuffer.reserve(4080);
+ llvm::raw_string_ostream Predefines(PredefineBuffer);
+ Predefines << PP.getPredefines();
+ MacroBuilder Builder(Predefines);
----------------
zahiraam wrote:
> aaron.ballman wrote:
> > I'm confused as to why we want to predefine this macro *only* when the
> > input source is stdin? So I'm not certain I understand why this change is
> > desired.
> >
> > e.g., https://godbolt.org/z/E8Y67381r (note how there's no
> > `__FLT_EVAL_METHOD__` defined there)
> I was offering a solution to the issue raised by @glandium in
> https://reviews.llvm.org/D109239. I thought that the issue was only when the
> source is stdin, but obviously not. The default setting should happen under
> no condition.
There have been a lot of reviews over this stuff, so I may be remembering
incorrectly... but I thought it was a conscious decision to *not* predefine
`__FLT_EVAL_METHOD__` because that value changes depending on pragmas in the
TU. I thought the way that macro worked was that we registered it as a macro
and we figure out its value at expansion time.
(The original report confused me into thinking that `__FLT_EVAL_METHOD__` was
behaving as though it was never defined, so expansion would never result in a
correct value except when the eval method is `0`.)
Repository:
rG LLVM Github Monorepo
CHANGES SINCE LAST ACTION
https://reviews.llvm.org/D124004/new/
https://reviews.llvm.org/D124004
_______________________________________________
cfe-commits mailing list
cfe-commits@lists.llvm.org
https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
