On Tue, 2016-10-11 at 06:34 -0400, Nathan Sidwell wrote:
> Hi,
> Jonathan & I were chatting at the cauldron about how -fmax-errors
> kills any
> notes about the final error. That's because we bail out just after
> emitting the
> final error. This patch fixes the problem by bailing out just before
> emitting
> the error or warning after that.
>
> Sure, we'll do slightly more compilation than asked for, but this is
> the fatal
> error path, so who cares how long it takes. Better to get notes to
> the user.
>
> I augmented the fmax-errors testcase so that the final emitted error
> has a
> trailing note (which we now emit), and is followed by a warning
> (which causes us
> to bail).
>
> The same logic applies to -Wfatal-errors handling.
>
> ok?
Thanks. Various comments inline below.
> 2016-10-11 Nathan Sidwell <nat...@acm.org>
>
> * diagnostic.c (diagnostic_action_after_output): Remove fatal
> and max error handling here ....
> (diagnostic_report_diagnostic): ... do it here instead.
>
> testsuite/
> * c-c++-common/fmax-errors.c: Add error with note.
>
> Index: diagnostic.c
> ===================================================================
> --- diagnostic.c (revision 240920)
> +++ diagnostic.c (working copy)
> @@ -464,24 +464,6 @@ diagnostic_action_after_output (diagnost
> case DK_SORRY:
> if (context->abort_on_error)
> real_abort ();
> - if (context->fatal_errors)
> - {
> - fnotice (stderr, "compilation terminated due to -Wfatal
-errors.\n");
> - diagnostic_finish (context);
> - exit (FATAL_EXIT_CODE);
> - }
> - if (context->max_errors != 0
> - && ((unsigned) (diagnostic_kind_count (context, DK_ERROR)
> - + diagnostic_kind_count (context,
DK_SORRY)
> - + diagnostic_kind_count (context,
DK_WERROR))
> - >= context->max_errors))
> - {
> - fnotice (stderr,
> - "compilation terminated due to -fmax
-errors=%u.\n",
> - context->max_errors);
> - diagnostic_finish (context);
> - exit (FATAL_EXIT_CODE);
> - }
> break;
>
> case DK_ICE:
> @@ -890,6 +872,25 @@ diagnostic_report_diagnostic (diagnostic
> return false;
> }
>
> + if (diagnostic->kind != DK_NOTE
> + && (unsigned)(diagnostic_kind_count (context, DK_ERROR)
> + + diagnostic_kind_count (context, DK_SORRY)
> + + diagnostic_kind_count (context, DK_WERROR))
> + >= (context->fatal_errors ? 1
> + : context->max_errors ? context->max_errors : ~0u))
Please simplify this conditional logic by breaking if up into multiple
nested if statements:
if (diagnostic->kind != DK_NOTE)
{
int count =
(diagnostic_kind_count (context, DK_ERROR)
+
diagnostic_kind_count (context, DK_SORRY)
+
diagnostic_kind_count (context, DK_WERROR);
or somesuch...
> + >= (context->fatal_errors ? 1
> + : context->max_errors ? context->max_errors : ~0u))
> + {
> + /* Check before emitting the diagnostic that would exceed the
> + limit. This way we will emit notes relevant to the final
> + emitted error. */
> + fnotice (stderr,
> + context->fatal_errors
> + ? "compilation terminated due to -Wfatal-errors.\n"
> + : "compilation terminated due to -fmax-errors=%u.\n",
> + context->max_errors);
> + diagnostic_finish (context);
> + exit (FATAL_EXIT_CODE);
> + }
This logic is running when the next diagnostic is about to be emitted.
But what if the user has selected -Wfatal-errors and there's a single
error and no further diagnostics? Could this change the observable
behavior? (I'm trying to think of a case here, but failing).
> context->lock++;
>
> if (diagnostic->kind == DK_ICE || diagnostic->kind == DK_ICE_NOBT)
> Index: testsuite/c-c++-common/fmax-errors.c
> ===================================================================
> --- testsuite/c-c++-common/fmax-errors.c (revision 240920)
> +++ testsuite/c-c++-common/fmax-errors.c (working copy)
> @@ -1,11 +1,13 @@
> /* PR c/44782 */
> /* { dg-do compile } */
> -/* { dg-options "-fmax-errors=3" } */
> +/* { dg-options "-fmax-errors=3 -Wall" } */
>
> void foo (unsigned int i, unsigned int j)
> {
> (i) (); /* { dg-error "" } */
> (j) (); /* { dg-error "" } */
> - (i+j) (); /* { dg-error "" } */
> + (k) (); /* { dg-error "" } */
> + /* { dg-message "identifier" "" { target c } 9 } */
> + i + j; /* no warning. */
> (i*j) (); /* no error here due to -fmax
-errors */
> } /* { dg-prune-output "compilation terminated" } */
Please can you add a comment about the dg-message directive, explaining
the intent. ("Verify that with -fmax-errors that a note associated
with the final error is still emitted", or somesuch").
Please can you add a testcase for -Wfatal-errors.
Thanks
Dave
