Re: C++ PATCH for c++/88216, ICE with class type in non-type template parameter
On 12/11/18 4:05 PM, Marek Polacek wrote: On Tue, Dec 11, 2018 at 10:48:17AM -0500, Jason Merrill wrote: On 12/10/18 2:52 PM, Marek Polacek wrote: + if (processing_template_decl && value_dependent_expression_p (expr)) You don't need to check processing_template_decl before value_dependent_expression_p. Ok. I would lean toward checking for value-dependence in convert_nontype_argument, which already does that a lot. Enough, actually, that perhaps we should remember the result in a local variable. I've moved the call, but I didn't add a local variable for the result, because I was afraid that, since EXPR is being modified on some of the codepaths, its value-dependent-ness (is that a term?) may change. Any change would be a bug, but the patch is OK as is. Jason
Re: C++ PATCH for c++/88216, ICE with class type in non-type template parameter
On Tue, Dec 11, 2018 at 10:48:17AM -0500, Jason Merrill wrote:
> On 12/10/18 2:52 PM, Marek Polacek wrote:
> > + if (processing_template_decl && value_dependent_expression_p (expr))
>
> You don't need to check processing_template_decl before
> value_dependent_expression_p.
Ok.
> I would lean toward checking for value-dependence in
> convert_nontype_argument, which already does that a lot. Enough, actually,
> that perhaps we should remember the result in a local variable.
I've moved the call, but I didn't add a local variable for the result,
because I was afraid that, since EXPR is being modified on some of the
codepaths, its value-dependent-ness (is that a term?) may change.
Thanks,
Bootstrapped/regtested on x86_64-linux, ok for trunk?
2018-12-11 Marek Polacek
PR c++/88216 - ICE with class type in non-type template parameter.
* mangle.c (write_expression): Handle TARGET_EXPR and
VIEW_CONVERT_EXPR.
* pt.c (convert_nontype_argument): Don't call
get_template_parm_object for value-dependent expressions.
* g++.dg/cpp2a/nontype-class9.C: New test.
diff --git gcc/cp/mangle.c gcc/cp/mangle.c
index 64415894bc5..56247883010 100644
--- gcc/cp/mangle.c
+++ gcc/cp/mangle.c
@@ -2836,13 +2836,21 @@ write_expression (tree expr)
{
enum tree_code code = TREE_CODE (expr);
+ if (TREE_CODE (expr) == TARGET_EXPR)
+{
+ expr = TARGET_EXPR_INITIAL (expr);
+ code = TREE_CODE (expr);
+}
+
/* Skip NOP_EXPR and CONVERT_EXPR. They can occur when (say) a pointer
argument is converted (via qualification conversions) to another type. */
while (CONVERT_EXPR_CODE_P (code)
|| location_wrapper_p (expr)
/* Parentheses aren't mangled. */
|| code == PAREN_EXPR
-|| code == NON_LVALUE_EXPR)
+|| code == NON_LVALUE_EXPR
+|| (code == VIEW_CONVERT_EXPR
+&& TREE_CODE (TREE_OPERAND (expr, 0)) == TEMPLATE_PARM_INDEX))
{
expr = TREE_OPERAND (expr, 0);
code = TREE_CODE (expr);
diff --git gcc/cp/pt.c gcc/cp/pt.c
index 8560e588593..3b378ee9ff4 100644
--- gcc/cp/pt.c
+++ gcc/cp/pt.c
@@ -7123,7 +7123,8 @@ convert_nontype_argument (tree type, tree expr,
tsubst_flags_t complain)
{
/* Replace the argument with a reference to the corresponding template
parameter object. */
- expr = get_template_parm_object (expr, complain);
+ if (!value_dependent_expression_p (expr))
+ expr = get_template_parm_object (expr, complain);
if (expr == error_mark_node)
return NULL_TREE;
}
diff --git gcc/testsuite/g++.dg/cpp2a/nontype-class9.C
gcc/testsuite/g++.dg/cpp2a/nontype-class9.C
new file mode 100644
index 000..737f712be47
--- /dev/null
+++ gcc/testsuite/g++.dg/cpp2a/nontype-class9.C
@@ -0,0 +1,29 @@
+// PR c++/88216
+// { dg-do compile { target c++2a } }
+
+template struct same;
+template struct same {};
+
+struct T { };
+
+template
+struct U { };
+
+template
+void f (U)
+{
+ same s;
+ same s2;
+}
+
+template
+U u;
+
+T t;
+U u2;
+
+void
+g ()
+{
+ f(u2);
+}
Re: C++ PATCH for c++/88216, ICE with class type in non-type template parameter
On 12/10/18 2:52 PM, Marek Polacek wrote: + if (processing_template_decl && value_dependent_expression_p (expr)) You don't need to check processing_template_decl before value_dependent_expression_p. I would lean toward checking for value-dependence in convert_nontype_argument, which already does that a lot. Enough, actually, that perhaps we should remember the result in a local variable. Jason
C++ PATCH for c++/88216, ICE with class type in non-type template parameter
Here we were crashing in cxx_eval_constant_expression:
4600 /* We can only get here in checking mode via
4601 build_non_dependent_expr, because any expression that
4602 calls or takes the address of the function will have
4603 pulled a FUNCTION_DECL out of the COMPONENT_REF. */
4604 gcc_checking_assert (ctx->quiet || errorcount);
4605 *non_constant_p = true;
4606 return t;
4607 }
where we got via
6661 if (!TREE_CONSTANT (expr))
6662 {
6663 if ((complain & tf_error)
6664 && require_rvalue_constant_expression (expr))
6665 cxx_constant_value (expr);
return error_mark_node;
6667 }
because the expr wasn't constant. The fix would be to add error() I think.
But the testcase is valid, so we need (also) something else. This problem
occurs when using a class type non-type template parameter as a template
argument, because the TREE_CONSTANT check in get_template_parm_object will
fail--we're in a template and build_converted_constant_expr didn't produce
a constant, because the expression contains template codes. So I thought
it would make sense to just return and create the template parameter object
at instantiation.
But then I was running into sorry() in the demangler so I had to make tweaks
there too. I don't know much about that code, so I hope I'm not doing anything
overly stoopid.
Bootstrapped/regtested on x86_64-linux, ok for trunk?
2018-12-10 Marek Polacek
PR c++/88216 - ICE with class type in non-type template parameter.
* mangle.c (write_expression): Handle TARGET_EXPR and
VIEW_CONVERT_EXPR.
* pt.c (get_template_parm_object): Just return for value dependent
expressions.
* g++.dg/cpp2a/nontype-class9.C: New test.
diff --git gcc/cp/mangle.c gcc/cp/mangle.c
index 64415894bc5..56247883010 100644
--- gcc/cp/mangle.c
+++ gcc/cp/mangle.c
@@ -2836,13 +2836,21 @@ write_expression (tree expr)
{
enum tree_code code = TREE_CODE (expr);
+ if (TREE_CODE (expr) == TARGET_EXPR)
+{
+ expr = TARGET_EXPR_INITIAL (expr);
+ code = TREE_CODE (expr);
+}
+
/* Skip NOP_EXPR and CONVERT_EXPR. They can occur when (say) a pointer
argument is converted (via qualification conversions) to another type. */
while (CONVERT_EXPR_CODE_P (code)
|| location_wrapper_p (expr)
/* Parentheses aren't mangled. */
|| code == PAREN_EXPR
-|| code == NON_LVALUE_EXPR)
+|| code == NON_LVALUE_EXPR
+|| (code == VIEW_CONVERT_EXPR
+&& TREE_CODE (TREE_OPERAND (expr, 0)) == TEMPLATE_PARM_INDEX))
{
expr = TREE_OPERAND (expr, 0);
code = TREE_CODE (expr);
diff --git gcc/cp/pt.c gcc/cp/pt.c
index 8560e588593..878a354b193 100644
--- gcc/cp/pt.c
+++ gcc/cp/pt.c
@@ -6655,6 +6655,9 @@ invalid_tparm_referent_p (tree type, tree expr,
tsubst_flags_t complain)
static tree
get_template_parm_object (tree expr, tsubst_flags_t complain)
{
+ if (processing_template_decl && value_dependent_expression_p (expr))
+return expr;
+
if (TREE_CODE (expr) == TARGET_EXPR)
expr = TARGET_EXPR_INITIAL (expr);
diff --git gcc/testsuite/g++.dg/cpp2a/nontype-class9.C
gcc/testsuite/g++.dg/cpp2a/nontype-class9.C
new file mode 100644
index 000..737f712be47
--- /dev/null
+++ gcc/testsuite/g++.dg/cpp2a/nontype-class9.C
@@ -0,0 +1,29 @@
+// PR c++/88216
+// { dg-do compile { target c++2a } }
+
+template struct same;
+template struct same {};
+
+struct T { };
+
+template
+struct U { };
+
+template
+void f (U)
+{
+ same s;
+ same s2;
+}
+
+template
+U u;
+
+T t;
+U u2;
+
+void
+g ()
+{
+ f(u2);
+}
