Preprocessor warnings printed with "errors" in provenance

[eyalroz]

• cppast version: main branch as of 2022-06-05
• parser: libclang_parser
• clang version: 11.0-51

I'm running tool/cppast on a program of mine, never mind the exact cmdline, and I get:

[preprocessor] [warning] /path/to/src/execution_context.hpp:42: unknown warning group '-Wclass-memaccess', ignored [-Wunknown-warning-option]
[preprocessor] [error] /path/to/src//util/warning_suppression.hpp:18: note: expanded from macro 'DISABLE_WARNING'
[preprocessor] [error] /path/to/src//util/warning_suppression.hpp:15: note: expanded from macro 'DO_PRAGMA'
[preprocessor] [error] <scratch space>:126: note: expanded from here

The warning might be legit, but - the "note: expanded from macro" messages should:

1. Not be printed as independent "items"
2. Not be printed as errors

as they are simply part of the text for the initial warning.

Also the "scratch space" might be dropped, or otherwise made more informative.

[foonathan]

Thanks, they're now reported as "info" and the scratchspace one is hidden.