tsubst_expr and tsubst_copy_and_build are not expected to handle
DEFERRED_NOEXCEPT exprs, but if tsubst_exception_specification takes a
DEFERRED_NOEXCEPT expr with !defer_ok, it just passes the expr on for
tsubst_copy_and_build to barf.
This patch arranges for tsubst_exception_specification to combine the
incoming args with those already stored in a DEFERRED_NOEXCEPT, and
then substitute them into the pattern, when retaining a deferred
noexcept is unacceptable.
Regstrapped on x86_64- and i686-linux-gnu, mistakenly along with a patch
with a known regression, and got only that known regression. Retesting
without it. Ok to install?
for gcc/cp/ChangeLog
PR c++/87814
* pt.c (tsubst_exception_specification): Handle
DEFERRED_NOEXCEPT with !defer_ok.
for gcc/testsuite/ChangeLog
PR c++/87814
* g++.dg/cpp1z/pr87814.C: New.
---
gcc/cp/pt.c | 14 +++++++++++---
gcc/testsuite/g++.dg/cpp1z/pr87814.C | 26 ++++++++++++++++++++++++++
2 files changed, 37 insertions(+), 3 deletions(-)
create mode 100644 gcc/testsuite/g++.dg/cpp1z/pr87814.C
diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c
index 8560e5885933..72ae7173d92c 100644
--- a/gcc/cp/pt.c
+++ b/gcc/cp/pt.c
@@ -14150,9 +14150,17 @@ tsubst_exception_specification (tree fntype,
}
}
else
- new_specs = tsubst_copy_and_build
- (expr, args, complain, in_decl, /*function_p=*/false,
- /*integral_constant_expression_p=*/true);
+ {
+ if (DEFERRED_NOEXCEPT_SPEC_P (specs))
+ {
+ args = add_to_template_args (DEFERRED_NOEXCEPT_ARGS (expr),
+ args);
+ expr = DEFERRED_NOEXCEPT_PATTERN (expr);
+ }
+ new_specs = tsubst_copy_and_build
+ (expr, args, complain, in_decl, /*function_p=*/false,
+ /*integral_constant_expression_p=*/true);
+ }
new_specs = build_noexcept_spec (new_specs, complain);
}
else if (specs)
diff --git a/gcc/testsuite/g++.dg/cpp1z/pr87814.C
b/gcc/testsuite/g++.dg/cpp1z/pr87814.C
new file mode 100644
index 000000000000..37034bb58cd6
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp1z/pr87814.C
@@ -0,0 +1,26 @@
+// { dg-do compile { target c++17 } }
+
+template<class Element>
+struct box {
+ template<class E>
+ constexpr box(E && e)
+ noexcept(noexcept(Element(e)))
+ {}
+};
+
+template<class... Ts>
+struct compressed_tuple_ : box<Ts> ... {
+ template<typename... Args>
+ constexpr compressed_tuple_(Args &&... args)
+ noexcept((noexcept(box<Ts>(args)) && ...))
+ : box<Ts>(args)...
+ {}
+};
+
+struct adaptor_cursor : compressed_tuple_<int*> {
+ using compressed_tuple_::compressed_tuple_;
+};
+
+int main() {
+ (void)noexcept(adaptor_cursor{(int*)0});
+}
--
Alexandre Oliva, freedom fighter https://FSFLA.org/blogs/lxo
Be the change, be Free! FSF Latin America board member
GNU Toolchain Engineer Free Software Evangelist
Hay que enGNUrecerse, pero sin perder la terGNUra jamás-GNUChe
