This was one of those PRs where the more you poke, the more ICEs turn up.
This patch fixes the ones I could find. The original problem was that
maybe_instantiate_noexcept got a TEMPLATE_DECL created for the member
friend template in do_friend. Its noexcept-specification was deferred,
so we went to the block with push_access_scope, but that crashes on a
TEMPLATE_DECL. One approach could be to somehow not defer noexcept-specs
for friend templates, I guess, but I didn't want to do that.
So the approach I did take in the end was to handle TEMPLATE_DECLs in
maybe_instantiate_noexcept.
That broke in register_parameter_specializations but we don't need this
code anyway, so let's do away with it -- the current_class_{ref,ptr}
code is enough to fix the PR that register_parameter_specializations was
introduced for.
Another issue was that since here we are instantiating a deferred noexcept,
in a instantiate_class_template context, processing_template_decl was 0.
Let's pretend it's on for the tsubst purposes here, and for build_noexcept_spec
too, so that the *_dependent_expression_p functions work.
Lastly, I found an invalid testcase that was breaking because a template code
leaked to constexpr functions. This I fixed similarly to the recent explicit
PR fix (r269131).
Bootstrapped/regtested on x86_64-linux, ok for trunk?
2019-03-07 Marek Polacek <[email protected]>
PR c++/89612 - ICE with member friend template with noexcept.
* except.c (build_noexcept_spec): Call instantiate_non_dependent_expr
before perform_implicit_conversion_flags. Add processing_template_decl
sentinel.
* pt.c (maybe_instantiate_noexcept): For function templates, use their
template result (function decl). Don't set up local specializations.
Temporarily turn on processing_template_decl. Update the template type
too.
* g++.dg/cpp0x/noexcept36.C: New test.
* g++.dg/cpp1y/noexcept1.C: New test.
* g++.dg/cpp1z/noexcept-type21.C: New test.
diff --git gcc/cp/except.c gcc/cp/except.c
index 139e871d7a7..d97b8d40542 100644
--- gcc/cp/except.c
+++ gcc/cp/except.c
@@ -1285,10 +1285,13 @@ build_noexcept_spec (tree expr, tsubst_flags_t complain)
if (TREE_CODE (expr) != DEFERRED_NOEXCEPT
&& !value_dependent_expression_p (expr))
{
+ expr = instantiate_non_dependent_expr_sfinae (expr, complain);
+ /* Don't let perform_implicit_conversion_flags create more template
+ codes. */
+ processing_template_decl_sentinel s;
expr = perform_implicit_conversion_flags (boolean_type_node, expr,
complain,
LOOKUP_NORMAL);
- expr = instantiate_non_dependent_expr (expr);
expr = cxx_constant_value (expr);
}
if (TREE_CODE (expr) == INTEGER_CST)
diff --git gcc/cp/pt.c gcc/cp/pt.c
index 906cfe0a58c..44a2c4606f8 100644
--- gcc/cp/pt.c
+++ gcc/cp/pt.c
@@ -24174,6 +24174,17 @@ maybe_instantiate_noexcept (tree fn, tsubst_flags_t
complain)
if (DECL_CLONED_FUNCTION_P (fn))
fn = DECL_CLONED_FUNCTION (fn);
+
+ tree orig_fn = NULL_TREE;
+ /* For a member friend template we can get a TEMPLATE_DECL. Let's use
+ its FUNCTION_DECL for the rest of this function -- push_access_scope
+ doesn't accept TEMPLATE_DECLs. */
+ if (DECL_FUNCTION_TEMPLATE_P (fn))
+ {
+ orig_fn = fn;
+ fn = DECL_TEMPLATE_RESULT (fn);
+ }
+
fntype = TREE_TYPE (fn);
spec = TYPE_RAISES_EXCEPTIONS (fntype);
@@ -24204,37 +24215,41 @@ maybe_instantiate_noexcept (tree fn, tsubst_flags_t
complain)
push_deferring_access_checks (dk_no_deferred);
input_location = DECL_SOURCE_LOCATION (fn);
- /* A new stack interferes with pop_access_scope. */
- {
- /* Set up the list of local specializations. */
- local_specialization_stack lss (lss_copy);
-
- tree save_ccp = current_class_ptr;
- tree save_ccr = current_class_ref;
- /* If needed, set current_class_ptr for the benefit of
- tsubst_copy/PARM_DECL. */
- tree tdecl = DECL_TEMPLATE_RESULT (DECL_TI_TEMPLATE (fn));
- if (DECL_NONSTATIC_MEMBER_FUNCTION_P (tdecl))
- {
- tree this_parm = DECL_ARGUMENTS (tdecl);
- current_class_ptr = NULL_TREE;
- current_class_ref = cp_build_fold_indirect_ref (this_parm);
- current_class_ptr = this_parm;
- }
+ tree save_ccp = current_class_ptr;
+ tree save_ccr = current_class_ref;
+ /* If needed, set current_class_ptr for the benefit of
+ tsubst_copy/PARM_DECL. */
+ tree tdecl = DECL_TEMPLATE_RESULT (DECL_TI_TEMPLATE (fn));
+ if (DECL_NONSTATIC_MEMBER_FUNCTION_P (tdecl))
+ {
+ tree this_parm = DECL_ARGUMENTS (tdecl);
+ current_class_ptr = NULL_TREE;
+ current_class_ref = cp_build_fold_indirect_ref (this_parm);
+ current_class_ptr = this_parm;
+ }
- /* Create substitution entries for the parameters. */
- register_parameter_specializations (tdecl, fn);
+ /* If this function is represented by a TEMPLATE_DECL, then
+ the deferred noexcept-specification might still contain
+ dependent types, even after substitution. And we need the
+ dependency check functions to work in build_noexcept_spec. */
+ if (orig_fn)
+ ++processing_template_decl;
- /* Do deferred instantiation of the noexcept-specifier. */
- noex = tsubst_copy_and_build (DEFERRED_NOEXCEPT_PATTERN (noex),
- DEFERRED_NOEXCEPT_ARGS (noex),
- tf_warning_or_error, fn,
- /*function_p=*/false,
- /*i_c_e_p=*/true);
- current_class_ptr = save_ccp;
- current_class_ref = save_ccr;
- spec = build_noexcept_spec (noex, tf_warning_or_error);
- }
+ /* Do deferred instantiation of the noexcept-specifier. */
+ noex = tsubst_copy_and_build (DEFERRED_NOEXCEPT_PATTERN (noex),
+ DEFERRED_NOEXCEPT_ARGS (noex),
+ tf_warning_or_error, fn,
+ /*function_p=*/false,
+ /*i_c_e_p=*/true);
+
+ current_class_ptr = save_ccp;
+ current_class_ref = save_ccr;
+
+ /* Build up the noexcept-specification. */
+ spec = build_noexcept_spec (noex, tf_warning_or_error);
+
+ if (orig_fn)
+ --processing_template_decl;
pop_deferring_access_checks ();
pop_access_scope (fn);
@@ -24250,6 +24265,8 @@ maybe_instantiate_noexcept (tree fn, tsubst_flags_t
complain)
return false;
TREE_TYPE (fn) = build_exception_variant (fntype, spec);
+ if (orig_fn)
+ TREE_TYPE (orig_fn) = TREE_TYPE (fn);
}
FOR_EACH_CLONE (clone, fn)
diff --git gcc/testsuite/g++.dg/cpp0x/noexcept36.C
gcc/testsuite/g++.dg/cpp0x/noexcept36.C
new file mode 100644
index 00000000000..ecab59df694
--- /dev/null
+++ gcc/testsuite/g++.dg/cpp0x/noexcept36.C
@@ -0,0 +1,19 @@
+// PR c++/89612
+// { dg-do compile { target c++11 } }
+
+template <typename>
+struct C {
+ template <int N>
+ friend int foo() noexcept(N);
+
+ template <int N>
+ friend int foo2() noexcept(N); // { dg-error "different exception" }
+};
+
+template <int N>
+int foo() noexcept(N);
+
+template <int N>
+int foo2() noexcept(N + 1);
+
+C<int> c;
diff --git gcc/testsuite/g++.dg/cpp1y/noexcept1.C
gcc/testsuite/g++.dg/cpp1y/noexcept1.C
new file mode 100644
index 00000000000..2344b1ba92c
--- /dev/null
+++ gcc/testsuite/g++.dg/cpp1y/noexcept1.C
@@ -0,0 +1,13 @@
+// PR c++/89612
+// { dg-do compile { target c++14 } }
+
+template <int> bool b;
+
+template <typename>
+struct C {
+ template <typename> friend int foo() noexcept(b<1>); // { dg-error "not
usable in a constant expression|different exception specifier" }
+};
+
+template <typename> int foo() noexcept(b<1>);
+
+auto a = C<int>();
diff --git gcc/testsuite/g++.dg/cpp1z/noexcept-type21.C
gcc/testsuite/g++.dg/cpp1z/noexcept-type21.C
new file mode 100644
index 00000000000..d0a61d95e87
--- /dev/null
+++ gcc/testsuite/g++.dg/cpp1z/noexcept-type21.C
@@ -0,0 +1,16 @@
+// PR c++/89612
+// { dg-do compile { target c++17 } }
+
+template <typename a> using b = typename a ::c;
+template <typename> bool d;
+template <typename, typename> struct e {
+ template <typename f, typename g> e(f, g) {}
+ template <typename h, typename i, typename j>
+ friend auto k(h &&, const j &, i &&) noexcept(d<b<h>, h> &&d<b<i>, i>);
+};
+template <typename l, typename m> e(l, m)->e<l, m>;
+template <typename l, typename m, typename j>
+auto k(l &&, const j &, m &&) noexcept(d<b<l>, l> &&d<b<m>, m>);
+int main() {
+ e(0, [] {});
+}
