__has_include with angle-bracketed argument breaks preprocessing

[dummyunit]

Preprocessing (in C++17 mode) of code like this:

#if __has_include(<any>)
#endif

results in an error:

/tmp/fail.cpp:1: syntax error: failed to evaluate #if condition

This happens regardless of whether the mentioned header file exists or not.

Debugging shows that <any> is split in 3 tokens: <, any, >, but the code for handling __has_include expects one token as argument: https://github.com/danmar/simplecpp/blob/ab680f96ea9aa0fc7ed241f6dc51954d7a8d6735/simplecpp.cpp
As a result the check to matching closing parenthesis fails (as any is not )) and a fatal syntax error is reported: https://github.com/danmar/simplecpp/blob/ab680f96ea9aa0fc7ed241f6dc51954d7a8d6735/simplecpp.cpp

This also affects Cppcheck - it reports preprocessorErrorDirective on that line and stops.

[danmar]

ouch I thought this __has_include was fixed by now. Thanks for reporting!

[jamesharris-garmin]

have we been able to fix this? or should someone submit a pull request?

Follow up: are we actually finding the correct file? in that code is it actually searching for < when we are searching the file? does it actually try to open any ?

[danmar]

I didn't have time to look at this yet. A PR would be appreciated.

Follow up:

not sure I'd have to look in the code and/or debug..

[aremmell]

No movement? Does someone externally need to PR this to get it done? It's pretty bad! This is a super common construct to use these days

[danmar]

No movement? Does someone externally need to PR this to get it done? It's pretty bad! This is a super common construct to use these days

This is an open source project. The development team is just a group of volounteers that helps out for free in their spare time.

I am hoping that Cppcheck Premium will grow and that we can someday pay some developer to work on Simplecpp and Cppcheck..

[aremmell]

Sorry, didn't mean to come off the wrong way. I was just surprised about this one. I would try to fix it myself if I thought I could without breaking 8 other things.

I imagine the learning curve is quite steep if you've never done something similar before. I can give it a go though if you want :)

[danmar]

Sorry, didn't mean to come off the wrong way.

ok.

I imagine the learning curve is quite steep if you've never done something similar before. I can give it a go though if you want :)

This code is not super trivial but imho this is probably a relatively nice task to start working with compared to some other tasks. Feel free to take a look I would appreciate a PR!

[aremmell]

Where would one start looking?

[danmar]

spontanously I wonder what happens here:

simplecpp/simplecpp.cpp

Line 3494 in b9bfbaa

if (hasInclude && tok->str() == HAS_INCLUDE) {

at a quick glance it looks as if <> is handled.

[danmar]

in this test case it looks like <> are handled:

simplecpp/test.cpp

Line 1312 in b9bfbaa

" #if __has_include(<realFileName1.cpp>)\n"

[danmar]

can somebody create a test case that fails? I don't get a syntax error here:

$ cat 229.cpp 
#if __has_include(<any>)
#endif
$ ./simplecpp 229.cpp 

$

[yut23]

The issues I was seeing with this seem to have been fixed by #271 (first included in cppcheck 2.10).

[danmar]

ok thanks.. I will close this.. if anybody still see problems feel free to reopen this issue or open a new issue..