c++: Fix ICE with delayed parsing of noexcept-specifier [PR95562]
authorMarek Polacek <polacek@redhat.com>
Tue, 9 Jun 2020 22:08:45 +0000 (18:08 -0400)
committerMarek Polacek <polacek@redhat.com>
Wed, 10 Jun 2020 13:36:02 +0000 (09:36 -0400)
Here we ICE because a DEFERRED_PARSE expression leaked to tsubst_copy.
We create these expressions for deferred noexcept-specifiers in
cp_parser_save_noexcept; they are supposed to be re-parsed in
cp_parser_late_noexcept_specifier.  In this case we never got around
to re-parsing it because the noexcept-specifier was attached to a
pointer to a function, not to a function declaration.  But we should
not have delayed the parsing here in the first place; we already
avoid delaying the parsing for alias-decls, typedefs, and friend
function declarations.  (Clang++ also doesn't delay the parsing
for pointers to function.)

gcc/cp/ChangeLog:

PR c++/95562
* parser.c (cp_parser_direct_declarator): Clear
CP_PARSER_FLAGS_DELAY_NOEXCEPT if the declarator kind is not
cdk_id.

gcc/testsuite/ChangeLog:

PR c++/95562
* g++.dg/cpp0x/noexcept60.C: New test.

gcc/cp/parser.c
gcc/testsuite/g++.dg/cpp0x/noexcept60.C [new file with mode: 0644]

index b0b31d2..bc66e6e 100644 (file)
@@ -21283,6 +21283,11 @@ cp_parser_direct_declarator (cp_parser* parser,
                    /* DR 1207: 'this' is in scope after the cv-quals.  */
                    inject_this_parameter (current_class_type, cv_quals);
 
+                 /* If it turned out that this is e.g. a pointer to a
+                    function, we don't want to delay noexcept parsing.  */
+                 if (declarator == NULL || declarator->kind != cdk_id)
+                   flags &= ~CP_PARSER_FLAGS_DELAY_NOEXCEPT;
+
                  /* Parse the exception-specification.  */
                  exception_specification
                    = cp_parser_exception_specification_opt (parser,
diff --git a/gcc/testsuite/g++.dg/cpp0x/noexcept60.C b/gcc/testsuite/g++.dg/cpp0x/noexcept60.C
new file mode 100644 (file)
index 0000000..d8efe1a
--- /dev/null
@@ -0,0 +1,13 @@
+// PR c++/95562
+// { dg-do compile { target c++11 } }
+
+template <bool Nothrow>
+struct Functions
+{
+  void (*func)(void*) noexcept(Nothrow);
+};
+
+void test()
+{
+  Functions<true> f{};
+}