[PATCH] c: Fix C cast error-recovery [PR101171]

Marek Polacek polacek@redhat.com
Thu Jun 24 13:24:33 GMT 2021


On Thu, Jun 24, 2021 at 12:11:23PM +0200, Jakub Jelinek wrote:
> Hi!
> 
> The following testcase ICEs during error-recovery, as build_c_cast calls
> note_integer_operands on error_mark_node and that wraps it into
> C_MAYBE_CONST_EXPR which is unexpected and causes ICE later on.
> Seems most other callers of note_integer_operands check early if something
> is error_mark_node and return before calling note_integer_operands on it.

Yeah.
 
> The following patch fixes it by not calling on error_mark_node, another
> possibility would be to handle error_mark_node in note_integer_operands and
> just return it.
> 
> Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?

This looks OK to me, thanks.
 
> 2021-06-24  Jakub Jelinek  <jakub@redhat.com>
> 
> 	PR c/101171
> 	* c-typeck.c (build_c_cast): Don't call note_integer_operands on
> 	error_mark_node.
> 
> 	* gcc.dg/pr101171.c: New test.
> 
> --- gcc/c/c-typeck.c.jj	2021-06-23 13:33:00.375434219 +0200
> +++ gcc/c/c-typeck.c	2021-06-23 17:51:17.501401208 +0200
> @@ -6131,6 +6131,7 @@ build_c_cast (location_t loc, tree type,
>       return value reflects this.  */
>    if (int_operands
>        && INTEGRAL_TYPE_P (type)
> +      && value != error_mark_node
>        && !EXPR_INT_CONST_OPERANDS (value))
>      value = note_integer_operands (value);
>  
> --- gcc/testsuite/gcc.dg/pr101171.c.jj	2021-06-23 17:56:53.409896019 +0200
> +++ gcc/testsuite/gcc.dg/pr101171.c	2021-06-23 17:56:28.668227851 +0200
> @@ -0,0 +1,13 @@
> +/* PR c/101171 */
> +/* { dg-do compile } */
> +/* { dg-options "" } */
> +
> +extern void foo (void);
> +int x = 0x1234;
> +
> +void
> +bar (void)
> +{
> +  if (x != (sizeof ((enum T) 0x1234)))	/* { dg-error "conversion to incomplete type" } */
> +    foo ();
> +}
> 
> 	Jakub
> 

Marek



More information about the Gcc-patches mailing list