c++: Treat OPAQUE_TYPE types as an aggregate type [PR97947]

MODE_OPAQUE and the associated OPAQUE_TYPE were added to stop the optimizers
from knowing how the bits in a variable with an opaque type are laid out.
This makes them a kind of pseudo aggregate type and we need to treat them
as such when we process the INIT initializer for variables with an
opaque type.

2020-12-02  Peter Bergner  <bergner@linux.ibm.com>

gcc/cp/
	PR c++/97947
	* typeck2.c (digest_init_r): Handle OPAQUE_TYPE as an aggregate type.

gcc/testsuite/
	PR c++/97947
	* g++.target/powerpc/pr97947.C: New test.

diff --git a/gcc/cp/typeck2.c b/gcc/cp/typeck2.c
index 575c609a365865a1d666464e394c0de82bc8329a..3fd2b1743332f9c6b0714774fe85323ebc4b973a 100644 (file)
--- a/gcc/cp/typeck2.c
+++ b/gcc/cp/typeck2.c
@@ -1150,6 +1150,7 @@ digest_init_r (tree type, tree init, int nested, int flags,
              || VECTOR_TYPE_P (type)
              || code == RECORD_TYPE
              || code == UNION_TYPE
+             || code == OPAQUE_TYPE
              || code == COMPLEX_TYPE);
 
   /* "If T is a class type and the initializer list has a single

diff --git a/gcc/testsuite/g++.target/powerpc/pr97947.C b/gcc/testsuite/g++.target/powerpc/pr97947.C
new file mode 100644 (file)
index 0000000..94e5ed6
--- /dev/null
+++ b/gcc/testsuite/g++.target/powerpc/pr97947.C
@@ -0,0 +1,12 @@
+/* PR c++/97947 */
+/* { dg-do compile } */
+/* { dg-require-effective-target power10_ok } */
+/* { dg-options "-O2 -mdejagnu-cpu=power10" } */
+
+/* Verify we do not ICE on the test below.  */
+
+void
+bug (__vector_pair *src)
+{
+  volatile __vector_pair dd = *src;
+}