diff mbox

Fix PR c++/62212 (ICE during mangling of array type)

Message ID 1458777830-16931-1-git-send-email-patrick@parcs.ath.cx
State New
Headers show

Commit Message

Patrick Palka March 24, 2016, 12:03 a.m. UTC 
When mangling an ARRAY_TYPE whose element type is a typedef variant and
whose domain is a type-dependent expression, we get an ICE when
canonicalize_for_substitution() tries to create a canonical version of
this ARRAY_TYPE with its element type being stripped of typedefs.

During this canonicalization we call build_cplus_array_type which builds
dependent and non-dependent array types differently.  But because at
this this point (during mangling) we are outside of a template decl, the
function wrongly thinks that the array type being built is non-dependent
according to dependent_type_p().  Because it's considered to be
non-dependent we build the type with build_array_type() which tries to
lay the type out and eventually we ICE because of its dependent TYPE_DOMAIN.

So to fix this, the check for type-dependentness in
build_cplus_array_type() should not depend on processing_template_decl.
This patch makes uses_template_parms() get used instead so that it
behaves properly outside of a template context, like during
mangling.

Does this look OK to commit after bootstrap + regtest?

gcc/cp/ChangeLog:

	PR c++/62212
	* tree.c (build_cplus_array_type): Determine type-dependentess
	with uses_template_parms instead of with dependent_type_p.

gcc/testsuite/ChangeLog:

	PR c++/62212
	* g++.dg/template/mangle2.C: New test.
---
 gcc/cp/tree.c                           |  5 ++---
 gcc/testsuite/g++.dg/template/mangle2.C | 19 +++++++++++++++++++
 2 files changed, 21 insertions(+), 3 deletions(-)
 create mode 100644 gcc/testsuite/g++.dg/template/mangle2.C

Comments

Jason Merrill March 24, 2016, 2:15 a.m. UTC | #1 
OK.

Jason
diff mbox

Patch

diff --git a/gcc/cp/tree.c b/gcc/cp/tree.c
index f784952..5d9de34 100644
--- a/gcc/cp/tree.c
+++ b/gcc/cp/tree.c
@@ -824,9 +824,8 @@  build_cplus_array_type (tree elt_type, tree index_type)
   if (elt_type == error_mark_node || index_type == error_mark_node)
     return error_mark_node;
 
-  bool dependent = (processing_template_decl
-		    && (dependent_type_p (elt_type)
-			|| (index_type && dependent_type_p (index_type))));
+  bool dependent = (uses_template_parms (elt_type)
+		    || (index_type && uses_template_parms (index_type)));
 
   if (elt_type != TYPE_MAIN_VARIANT (elt_type))
     /* Start with an array of the TYPE_MAIN_VARIANT.  */
diff --git a/gcc/testsuite/g++.dg/template/mangle2.C b/gcc/testsuite/g++.dg/template/mangle2.C
new file mode 100644
index 0000000..50b0d9f
--- /dev/null
+++ b/gcc/testsuite/g++.dg/template/mangle2.C
@@ -0,0 +1,19 @@ 
+// PR c++/62212
+// { dg-do assemble }
+
+typedef int my_int;
+
+template<typename T>
+struct X {
+    enum {value = 1};
+};
+
+template<typename T>
+void f(const my_int(&)[X<T>::value]);
+
+int main() {
+    const my_int a[1] = {};
+    f<void>(a);
+}
+
+// { dg-final { scan-assembler "_Z1fIvEvRAsr1XIT_E5value_Ki" } }