[MacPorts] #57578: __has_feature(cxx_exceptions) returns true but fails to compile std::uncaught_exceptions()

[MacPorts]

#57578: __has_feature(cxx_exceptions) returns true but fails to compile
std::uncaught_exceptions()
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  Reporter:  noloader   |      Owner:  jeremyhu
      Type:  defect     |     Status:  assigned
  Priority:  Normal     |  Milestone:
 Component:  ports      |    Version:
Resolution:             |   Keywords:
      Port:  clang-6.0  |
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Comment (by jmroot):

 Replying to [ticket:57578 noloader]:
 > According to the LLVM 3.6 release notes
 (https://releases.llvm.org/3.6.0/tools/clang/docs/ReleaseNotes.html#the-
 exceptions-macro), I believe I am using the correct feature test:
 >
 >     To reliably test if C++ exceptions are enabled,
 >     use `__EXCEPTIONS && __has_feature(cxx_exceptions)`,
 >     else things won’t work in all versions of Clang in
 >     Objective-C++ files.

 This doesn't say anything about C++17 features, just that it tells you
 whether C++ exceptions are enabled at all. Since uncaught_exceptions is
 part of the standard library and not the compiler, I would guess its
 absence isn't a problem with clang++ as such.

-- 
Ticket URL: <https://trac.macports.org/ticket/57578#comment:6>
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