[Bug c++/77462] Error message prints source from wrong file after #line

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77462

Andrew Pinski  changed:

   What|Removed |Added

 Status|NEW |RESOLVED
 Resolution|--- |INVALID

--- Comment #3 from Andrew Pinski  ---
Hmm, I think this is expected.  Take a good example of why #line are used in
the first place: generated files.

IF you are playing preprocessor tricks like this, you get what you deserve in
the error message.  

In fact I would say clang got it all wrong.

[Bug c++/77462] Error message prints source from wrong file after #line

[d.frey at gmx dot de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77462

--- Comment #2 from Daniel Frey  ---
(In reply to Manuel López-Ibáñez from comment #1)

Indeed, this is even worse than I thought.

FWIW, here's a reduced example for my code:

  static_assert( 2 + 2 == 4, "oops" );
  #line 1
  static_assert( 2 + 2 == 5, "oops" );

Leading to the same wrong error message, no explicit setting of the file is
necessary to confuse the compiler.

[Bug c++/77462] Error message prints source from wrong file after #line

[manu at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77462

Manuel López-Ibáñez  changed:

   What|Removed |Added

   Keywords||diagnostic
 Status|UNCONFIRMED |NEW
   Last reconfirmed||2016-09-02
 CC||manu at gcc dot gnu.org
 Ever confirmed|0   |1

--- Comment #1 from Manuel López-Ibáñez  ---
I'm pretty sure there was an open bug already about this but I cannot find it.

What is even worse is that, even without #line, we cannot display the caret
line if the file is preprocessed and the original files cannot be found:

# 1 "filenotavailable.cc"
# 1 ""
# 1 ""
# 1 "/usr/include/stdc-predef.h" 1 3 4
# 1 "" 2
# 1 "filenotavailable.cc"
int main()
{
  static_assert( 2 + 2 == 5, "oops" );
}

$ g++ filenotavailable.ii -std=c++11
filenotavailable.cc: In function ‘int main()’:
filenotavailable.cc:3:3: error: static assertion failed: oops