On Mon, 2018-11-12 at 13:37 -0700, Martin Sebor wrote: > On 11/11/2018 07:43 PM, David Malcolm wrote: > > We often emit more than one diagnostic at the same source location. > > For example, the C++ frontend can emit many diagnostics at > > the same source location when suggesting overload candidates. > > > > For example: > > > > ../../src/gcc/testsuite/g++.dg/diagnostic/bad-binary-ops.C: In > > function 'int test_3(s, t)': > > ../../src/gcc/testsuite/g++.dg/diagnostic/bad-binary-ops.C:38:18: > > error: no match for 'operator&&' (operand types are 's' and 't') > > 38 | return param_s && param_t; > > | ~~~~~~~~^~~~~~~~~~ > > ../../src/gcc/testsuite/g++.dg/diagnostic/bad-binary-ops.C:38:18: > > note: candidate: 'operator&&(bool, bool)' <built-in> > > ../../src/gcc/testsuite/g++.dg/diagnostic/bad-binary-ops.C:38:18: > > note: no known conversion for argument 2 from 't' to 'bool' > > > > This is overly verbose. Note how the same location has been > > printed > > three times, obscuring the pertinent messages. > > > > This patch add a new "elide" value to -fdiagnostics-show-location= > > and makes it the default (previously it was "once"). With elision > > the above is printed as: > > > > ../../src/gcc/testsuite/g++.dg/diagnostic/bad-binary-ops.C: In > > function 'int test_3(s, t)': > > ../../src/gcc/testsuite/g++.dg/diagnostic/bad-binary-ops.C:38:18: > > error: no match for 'operator&&' (operand types are 's' and 't') > > 38 | return param_s && param_t; > > | ~~~~~~~~^~~~~~~~~~ > > = note: candidate: 'operator&&(bool, bool)' <built-in> > > = note: no known conversion for argument 2 from 't' to > > 'bool' > > > > where the followup notes are printed with a '=' lined up with > > the source code margin. > > > > Thoughts? > > I agree the long pathname in the notes is at first glance redundant > but I'm not sure about using '=' as a shorthand for it. I have > written many scripts to parse GCC output to extract all diagnostics > (including notes) and publish those on a Web page somewhere, as I'm > sure must have others. All those scripts would stop working with > this change and require changes to the build system to work again. > Making those changes can be a substantial undertaking in some > organizations. > > Have you considered printing just the file name instead? Or any > other alternatives?
"-fdiagnostics-show-location=once" will restore the old behavior. Alternatively, if you want to parse GCC output, I'm adding a JSON output format; see: https://gcc.gnu.org/ml/gcc-patches/2018-11/msg01038.html (I'm testing an updated version of that patch) Dave
