backport: re PR c++/85208 (ICE with #pragma weak and structured binding)

	Backported from mainline
	2018-04-05  Jakub Jelinek  <jakub@redhat.com>

	PR c++/85208
	* decl.c (start_decl): For DECL_DECOMPOSITION_P decls, don't call
	maybe_apply_pragma_weak here...
	(cp_maybe_mangle_decomp): ... but call it here instead.

	* g++.dg/cpp1z/decomp41.C: New test.

From-SVN: r261948

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index a3bec6f431406f4a8bc2e346aad775e58dc87bcc..6b08634faa20c932ed3784119050168bb12d463f 100644 (file)
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,6 +1,13 @@
 2018-06-22  Jakub Jelinek  <jakub@redhat.com>
 
        Backported from mainline
+       2018-04-05  Jakub Jelinek  <jakub@redhat.com>
+
+       PR c++/85208
+       * decl.c (start_decl): For DECL_DECOMPOSITION_P decls, don't call
+       maybe_apply_pragma_weak here...
+       (cp_maybe_mangle_decomp): ... but call it here instead.
+
        2018-04-04  Jakub Jelinek  <jakub@redhat.com>
 
        PR inline-asm/85172

diff --git a/gcc/cp/decl.c b/gcc/cp/decl.c
index 2193dd929f852e92f5fcf2b5341a8b9a573150bc..950e04a668070e5d9dde361b5878e3c2e7a3c078 100644 (file)
--- a/gcc/cp/decl.c
+++ b/gcc/cp/decl.c
@@ -5022,7 +5022,7 @@ start_decl (const cp_declarator *declarator,
     }
 
   /* If #pragma weak was used, mark the decl weak now.  */
-  if (!processing_template_decl)
+  if (!processing_template_decl && !DECL_DECOMPOSITION_P (decl))
     maybe_apply_pragma_weak (decl);
 
   if (TREE_CODE (decl) == FUNCTION_DECL
@@ -7422,6 +7422,7 @@ cp_maybe_mangle_decomp (tree decl, tree first, unsigned int count)
       for (unsigned int i = 0; i < count; i++, d = DECL_CHAIN (d))
        v[count - i - 1] = d;
       SET_DECL_ASSEMBLER_NAME (decl, mangle_decomp (decl, v));
+      maybe_apply_pragma_weak (decl);
     }
 }
 

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 25011ca786d5dd710f347a05faa6ee7c00d5854a..669b4bed1b72f31518fe0e1731965507a792c4eb 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,6 +1,11 @@
 2018-06-22  Jakub Jelinek  <jakub@redhat.com>
 
        Backported from mainline
+       2018-04-05  Jakub Jelinek  <jakub@redhat.com>
+
+       PR c++/85208
+       * g++.dg/cpp1z/decomp41.C: New test.
+
        2018-04-04  Jakub Jelinek  <jakub@redhat.com>
 
        PR inline-asm/85172

diff --git a/gcc/testsuite/g++.dg/cpp1z/decomp41.C b/gcc/testsuite/g++.dg/cpp1z/decomp41.C
new file mode 100644 (file)
index 0000000..1ce836b
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp1z/decomp41.C
@@ -0,0 +1,9 @@
+// PR c++/85208
+// { dg-do compile { target c++11 } }
+// { dg-require-weak "" }
+// { dg-options "" }
+
+#pragma weak _ZDC1d1e1fE
+struct A { int i, j, k; };
+auto [a, b, c] = A (); // { dg-warning "decomposition declaration only available with" "" { target c++14_down } }
+auto [d, e, f] = A (); // { dg-warning "decomposition declaration only available with" "" { target c++14_down } }