Fix build error with g++ 6.3 (Debian Stretch) - #357
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The problem with this patch is the compiler can ignore f() if it's unused. That'd mean it trades your false negative error case to a false positive error for others. Can you try a different approach? I'd expect a simple cast to work just fine (e.g., return (int)f();). |
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travis-ci failure: Not sure what happened, but appears unrelated to the change. Been a looong time since I did much of anything with stepcode. As for appveyor, I'm not sure it ever worked :/ |
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I have updated this pull request to address @brlcad's suggestion. |
On this platform, TEST_NULLPTR fails, even though nullptr and
nullptr_t are supported:
/home/jepler/src/stepcode/build/CMakeFiles/CMakeTmp/src.cxx:4:23:
error: converting to 'bool' from 'std::nullptr_t'
requires direct-initialization [-fpermissive]
int main() {return !!f();}
~^~
Subsequent to this failure, the workaround definitions in sc_nullptr.h
prevent standard C++ headers (which must refer to real nullptr) to fail.
The failure occurs because the C++ standard apparently does not state
that operator! may be used on nullptr. Despite this, some compilers
have historically allowed it. g++ 6.3's behavior appears to be aligned
with the standard.
As requested by @brlcad, ensure that the function 'f' is used from main,
to avoid a clever (but not nullptr-supporting) compiler from somehow
skipping 'f' altogether, creating a false positive for nullptr support.
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On this platform, TEST_NULLPTR fails, even though nullptr and
nullptr_t are supported:
Subsequent to this failure, the workaround definitions in sc_nullptr.h
prevent standard C++ headers (which must refer to real nullptr) from
compiling.
The failure occurs because the C++ standard apparently does not state
that operator! may be used on nullptr. Despite this, some compilers
have historically allowed it. g++ 6.3's behavior appears to be aligned
with the standard.