[PATCH] Fix missing warning with bool (PR c/67854)
The following is another issue with macros from system headers. In this case
bool is defined in a system header to expand to _Bool and the "is promoted to"
warning didn't trigger because of that. The fix is to use the expanded
location.
Bootstrapped/regtested on x86_64-linux, ok for trunk?
2016-02-24 Marek Polacek
PR c/67854
* gimplify.c (gimplify_va_arg_expr): Use expanded location for the
"is promoted to" warning.
* gcc.dg/pr67854.c: New test.
diff --git gcc/gimplify.c gcc/gimplify.c
index 7be6bd7..e7ea974 100644
--- gcc/gimplify.c
+++ gcc/gimplify.c
@@ -11573,24 +11573,28 @@ gimplify_va_arg_expr (tree *expr_p, gimple_seq *pre_p,
{
static bool gave_help;
bool warned;
+ /* Use the expansion point to handle cases such as passing bool (defined
+in a system header) through `...'. */
+ source_location xloc
+ = expansion_point_location_if_in_system_header (loc);
/* Unfortunately, this is merely undefined, rather than a constraint
violation, so we cannot make this an error. If this call is never
executed, the program is still strictly conforming. */
- warned = warning_at (loc, 0,
- "%qT is promoted to %qT when passed through %<...%>",
+ warned = warning_at (xloc, 0,
+ "%qT is promoted to %qT when passed through %<...%>",
type, promoted_type);
if (!gave_help && warned)
{
gave_help = true;
- inform (loc, "(so you should pass %qT not %qT to %)",
+ inform (xloc, "(so you should pass %qT not %qT to %)",
promoted_type, type);
}
/* We can, however, treat "undefined" any way we please.
Call abort to encourage the user to fix the program. */
if (warned)
- inform (loc, "if this code is reached, the program will abort");
+ inform (xloc, "if this code is reached, the program will abort");
/* Before the abort, allow the evaluation of the va_list
expression to exit or longjmp. */
gimplify_and_add (valist, pre_p);
diff --git gcc/testsuite/gcc.dg/pr67854.c gcc/testsuite/gcc.dg/pr67854.c
index e69de29..af994c6 100644
--- gcc/testsuite/gcc.dg/pr67854.c
+++ gcc/testsuite/gcc.dg/pr67854.c
@@ -0,0 +1,11 @@
+/* PR c/67854 */
+/* { dg-do compile } */
+
+#include
+#include
+
+void
+foo (va_list ap)
+{
+ va_arg (ap, bool); /* { dg-warning "is promoted to .int. when passed
through" } */
+}
Marek
Re: [PATCH] Fix missing warning with bool (PR c/67854)
Ping.
On Wed, Feb 24, 2016 at 05:31:22PM +0100, Marek Polacek wrote:
> The following is another issue with macros from system headers. In this case
> bool is defined in a system header to expand to _Bool and the "is promoted to"
> warning didn't trigger because of that. The fix is to use the expanded
> location.
>
> Bootstrapped/regtested on x86_64-linux, ok for trunk?
>
> 2016-02-24 Marek Polacek
>
> PR c/67854
> * gimplify.c (gimplify_va_arg_expr): Use expanded location for the
> "is promoted to" warning.
>
> * gcc.dg/pr67854.c: New test.
>
> diff --git gcc/gimplify.c gcc/gimplify.c
> index 7be6bd7..e7ea974 100644
> --- gcc/gimplify.c
> +++ gcc/gimplify.c
> @@ -11573,24 +11573,28 @@ gimplify_va_arg_expr (tree *expr_p, gimple_seq
> *pre_p,
> {
>static bool gave_help;
>bool warned;
> + /* Use the expansion point to handle cases such as passing bool
> (defined
> + in a system header) through `...'. */
> + source_location xloc
> + = expansion_point_location_if_in_system_header (loc);
>
>/* Unfortunately, this is merely undefined, rather than a constraint
>violation, so we cannot make this an error. If this call is never
>executed, the program is still strictly conforming. */
> - warned = warning_at (loc, 0,
> -"%qT is promoted to %qT when passed through %<...%>",
> + warned = warning_at (xloc, 0,
> +"%qT is promoted to %qT when passed through %<...%>",
> type, promoted_type);
>if (!gave_help && warned)
> {
> gave_help = true;
> - inform (loc, "(so you should pass %qT not %qT to %)",
> + inform (xloc, "(so you should pass %qT not %qT to %)",
> promoted_type, type);
> }
>
>/* We can, however, treat "undefined" any way we please.
>Call abort to encourage the user to fix the program. */
>if (warned)
> - inform (loc, "if this code is reached, the program will abort");
> + inform (xloc, "if this code is reached, the program will abort");
>/* Before the abort, allow the evaluation of the va_list
>expression to exit or longjmp. */
>gimplify_and_add (valist, pre_p);
> diff --git gcc/testsuite/gcc.dg/pr67854.c gcc/testsuite/gcc.dg/pr67854.c
> index e69de29..af994c6 100644
> --- gcc/testsuite/gcc.dg/pr67854.c
> +++ gcc/testsuite/gcc.dg/pr67854.c
> @@ -0,0 +1,11 @@
> +/* PR c/67854 */
> +/* { dg-do compile } */
> +
> +#include
> +#include
> +
> +void
> +foo (va_list ap)
> +{
> + va_arg (ap, bool); /* { dg-warning "is promoted to .int. when passed
> through" } */
> +}
>
> Marek
Marek
Re: [PATCH] Fix missing warning with bool (PR c/67854)
On 02/24/2016 09:31 AM, Marek Polacek wrote: The following is another issue with macros from system headers. In this case bool is defined in a system header to expand to _Bool and the "is promoted to" warning didn't trigger because of that. The fix is to use the expanded location. Bootstrapped/regtested on x86_64-linux, ok for trunk? 2016-02-24 Marek Polacek PR c/67854 * gimplify.c (gimplify_va_arg_expr): Use expanded location for the "is promoted to" warning. * gcc.dg/pr67854.c: New test. This isn't a regression, so I put it in my gcc-7 bucket. Is this something we really need to address in gcc-6? FWIW, I think the patch is technically fine. Jeff
Re: [PATCH] Fix missing warning with bool (PR c/67854)
On Tue, Mar 01, 2016 at 09:31:26AM -0700, Jeff Law wrote: > On 02/24/2016 09:31 AM, Marek Polacek wrote: > >The following is another issue with macros from system headers. In this case > >bool is defined in a system header to expand to _Bool and the "is promoted > >to" > >warning didn't trigger because of that. The fix is to use the expanded > >location. > > > >Bootstrapped/regtested on x86_64-linux, ok for trunk? > > > >2016-02-24 Marek Polacek > > > > PR c/67854 > > * gimplify.c (gimplify_va_arg_expr): Use expanded location for the > > "is promoted to" warning. > > > > * gcc.dg/pr67854.c: New test. > This isn't a regression, so I put it in my gcc-7 bucket. Is this something > we really need to address in gcc-6? Well, gcc4.7 warned, the warning disappeared in gcc4.8, so I think this is a regression. I'm fine with deferring to 7 though. > FWIW, I think the patch is technically fine. Thanks, Marek
Re: [PATCH] Fix missing warning with bool (PR c/67854)
On Tue, Mar 01, 2016 at 08:08:03PM +0100, Marek Polacek wrote: > On Tue, Mar 01, 2016 at 09:31:26AM -0700, Jeff Law wrote: > > On 02/24/2016 09:31 AM, Marek Polacek wrote: > > >The following is another issue with macros from system headers. In this > > >case > > >bool is defined in a system header to expand to _Bool and the "is promoted > > >to" > > >warning didn't trigger because of that. The fix is to use the expanded > > >location. > > > > > >Bootstrapped/regtested on x86_64-linux, ok for trunk? > > > > > >2016-02-24 Marek Polacek > > > > > > PR c/67854 > > > * gimplify.c (gimplify_va_arg_expr): Use expanded location for the > > > "is promoted to" warning. > > > > > > * gcc.dg/pr67854.c: New test. > > This isn't a regression, so I put it in my gcc-7 bucket. Is this something > > we really need to address in gcc-6? > > Well, gcc4.7 warned, the warning disappeared in gcc4.8, so I think this is > a regression. I'm fine with deferring to 7 though. > > > FWIW, I think the patch is technically fine. > > Thanks, This is ok for trunk. Jakub
