[committed] openmp: Don't try to destruct DECL_OMP_PRIVATIZED_MEMBER vars [PR108180]

[Jakub Jelinek <jakub@redhat.com>]

Hi!

DECL_OMP_PRIVATIZED_MEMBER vars are artificial vars with DECL_VALUE_EXPR
of this->field used just during gimplification and omp lowering/expansion
to privatize individual fields in methods when needed.
As the following testcase shows, when not in templates, they were handled
right, but in templates we actually called cp_finish_decl on them and
that can result in their destruction, which is obviously undesirable,
we should only destruct the privatized copies of them created in omp
lowering.

Fixed thusly.

Bootstrapped/regtested on x86_64-linux and i686-linux, committed to trunk
so far.

2022-12-21  Jakub Jelinek  <jakub@redhat.com>

	PR c++/108180
	* pt.cc (tsubst_expr): Don't call cp_finish_decl on
	DECL_OMP_PRIVATIZED_MEMBER vars.

	* testsuite/libgomp.c++/pr108180.C: New test.

--- gcc/cp/pt.cc.jj	2022-12-19 11:09:13.499170642 +0100
+++ gcc/cp/pt.cc	2022-12-20 12:13:59.406097521 +0100
@@ -18895,6 +18895,11 @@ tsubst_expr (tree t, tree args, tsubst_f
 		    maybe_push_decl (decl);
 
 		    if (VAR_P (decl)
+			&& DECL_LANG_SPECIFIC (decl)
+			&& DECL_OMP_PRIVATIZED_MEMBER (decl))
+		      break;
+
+		    if (VAR_P (decl)
 			&& DECL_DECOMPOSITION_P (decl)
 			&& TREE_TYPE (pattern_decl) != error_mark_node)
 		      ndecl = tsubst_decomp_names (decl, pattern_decl, args,
--- libgomp/testsuite/libgomp.c++/pr108180.C.jj	2022-12-20 12:54:21.077793817 +0100
+++ libgomp/testsuite/libgomp.c++/pr108180.C	2022-12-20 12:53:04.740905961 +0100
@@ -0,0 +1,55 @@
+// PR c++/108180
+// { dg-do run }
+
+struct A {
+  A () { ++a; }
+  A (A &&) = delete;
+  A (const A &) { ++a; }
+  A &operator= (const A &) = delete;
+  A &operator= (A &&) = delete;
+  ~A () { --a; }
+  static int a;
+};
+int A::a = 0;
+
+struct B {
+  A a;
+  template <int N>
+  int
+  foo ()
+  {
+    int res = 0;
+    #pragma omp parallel for if(false) firstprivate(a)
+    for (int i = 0; i < 64; ++i)
+      res += i;
+    return res;
+  }
+  int
+  bar ()
+  {
+    int res = 0;
+    #pragma omp parallel for if(false) firstprivate(a)
+    for (int i = 0; i < 64; ++i)
+      res += i;
+    return res;
+  }
+};
+
+int
+main ()
+{
+  {
+    B b;
+    if (b.foo<0> () != 2016)
+      __builtin_abort ();
+  }
+  if (A::a != 0)
+    __builtin_abort ();
+  {
+    B b;
+    if (b.bar () != 2016)
+      __builtin_abort ();
+  }
+  if (A::a != 0)
+    __builtin_abort ();
+}

	Jakub