From patchwork Sun Oct 31 21:34:14 2010
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Subject: use build_vector_from_val in more places
Date: Sun, 31 Oct 2010 11:34:14 -0000
From: Nathan Froyd <froydnj@codesourcery.com>
X-Patchwork-Id: 69740
Message-Id: <20101031213413.GG6758@nightcrawler>
To: Uros Bizjak <ubizjak@gmail.com>
Cc: gcc-patches@gcc.gnu.org, Diego Novillo <dnovillo@google.com>

On Sun, Oct 31, 2010 at 09:51:41AM +0100, Uros Bizjak wrote:
> > The recently-introduced build_vector_from_val function can be used in
> > several places, centralizing TREE_LIST use and making it easier to
> > remove at a later point.  The assertion change in build_vector_from_val
> > is needed so as to not ICE while building libgfortran and is, I think,
> > more correct in any event.
> 
> This patch caused a regression on x86_64-pc-linux-gnu [1]:
> 
> FAIL: gcc.dg/torture/pr45720.c  -O2 -flto  (internal compiler error)
> FAIL: gcc.dg/torture/pr45720.c  -O2 -flto  (test for excess errors)
> FAIL: gcc.dg/torture/pr45720.c  -O2 -fwhopr  (internal compiler error)
> FAIL: gcc.dg/torture/pr45720.c  -O2 -fwhopr  (test for excess errors)
> 
> You can trigger this ICE using following command sequence:
> 
> $ <path>/gcc/xgcc -B <path>/gcc -O2 -flto -ftree-vectorize -c pr45720.c
> $ <path>/gcc/lto1 -O2 -ftree-vectorize -quiet pr45720.o

Whoops!  Apologies for the breakage.  I think this is because there is
no types_compatible_p hook for LTO, which makes sense.

The below patch makes the assert use useless_type_conversion_p instead.
Third time's the charm for such a simple assert...

The patch fixes the above ICEs.  Full testing in progress on
x86_64-unknown-linux-gnu.  OK to commit?

-Nathan

	* tree.c (build_vector_from_val): Use useless_type_conversion_p.


diff --git a/gcc/tree.c b/gcc/tree.c
index 4de73ee..a746031 100644
--- a/gcc/tree.c
+++ b/gcc/tree.c
@@ -1376,8 +1376,8 @@ build_vector_from_val (tree vectype, tree sc)
   if (sc == error_mark_node)
     return sc;
 
-  gcc_assert (lang_hooks.types_compatible_p (TREE_TYPE (sc),
-					     TREE_TYPE (vectype)));
+  gcc_assert (useless_type_conversion_p (TREE_TYPE (sc),
+					 TREE_TYPE (vectype)));
 
   v = VEC_alloc (constructor_elt, gc, nunits);
   for (i = 0; i < nunits; ++i)