[Bug c++/62161] more precise locations for command-line diagnostics

[dmalcolm at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=62161

David Malcolm <dmalcolm at gcc dot gnu.org> changed:

           What    |Removed                     |Added
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                 CC|                            |dmalcolm at gcc dot gnu.org

--- Comment #1 from David Malcolm <dmalcolm at gcc dot gnu.org> ---
Given that the driver takes the user-supplied command line and uses it to
invoke cc1 etc, the command-line seen by cc1 doesn't bear a simple relationship
to the one the user provided.

So I don't know if there's a good way to implement this.

Notes:

c-opts.c:c_finish_options creates the <command-line> linemap by calling:

1381          cb_file_change (parse_in,
1382                          linemap_check_ordinary (linemap_add (line_table,
LC_RENAME, 0,
1383                                                              
_("<command-line>"), 0)));