Hello!
Attached is a patch that fixes an ICE on the devel/c++-modules branch caused
by a slot invalidation edge case in push_namespace.
It's been sitting around for a while and I wasn't sure if I should use the
original date or not. Feel free to adjust that to the commit date if that's
what it should be instead.
2020-05-15 Jeff Chapman II <jchap...@lock3software.com>
gcc/cp/
* name-lookup.c (push_namespace): Fix slot invalidation related
ICE when compiling with modules enabled.
gcc/testsuite/
* g++.dg/modules/string-view1.C: New test.
* g++.dg/modules/string-view2.C: Ditto.
Please let me know if there's anything more I can do,
Jeff Chapman II
From d33a239c187cb6cef1c39953c5f014bd266492de Mon Sep 17 00:00:00 2001
From: Jeff Chapman II <jchap...@lock3software.com>
Date: Fri, 15 May 2020 06:37:41 -0400
Subject: [PATCH 1/1] c++: Fix push_namespace ICE with modules
push_namespace was reusing an earlier find_namespace_slot result after
it was invalidated by pushdecl in corner cases.
2020-05-15 Jeff Chapman II <jchap...@lock3software.com>
gcc/cp/
* name-lookup.c (push_namespace): Fix slot invalidation related
ICE when compiling with modules enabled.
gcc/testsuite/
* g++.dg/modules/string-view1.C: New test.
* g++.dg/modules/string-view2.C: Ditto.
---
gcc/cp/name-lookup.c | 2 +
gcc/testsuite/g++.dg/modules/string-view1.C | 6 +++
gcc/testsuite/g++.dg/modules/string-view2.C | 53 +++++++++++++++++++++
3 files changed, 61 insertions(+)
create mode 100644 gcc/testsuite/g++.dg/modules/string-view1.C
create mode 100644 gcc/testsuite/g++.dg/modules/string-view2.C
diff --git a/gcc/cp/name-lookup.c b/gcc/cp/name-lookup.c
index e9495d2a282..462f028617c 100644
--- a/gcc/cp/name-lookup.c
+++ b/gcc/cp/name-lookup.c
@@ -8920,6 +8920,8 @@ push_namespace (tree name, bool make_inline)
{
/* finish up making the namespace. */
add_decl_to_level (NAMESPACE_LEVEL (current_namespace), ns);
+ /* pushdecl may invalidate slot, find name again. */
+ slot = find_namespace_slot (current_namespace, name, true);
make_namespace_finish (ns, slot);
/* Add the anon using-directive here, we don't do it in
diff --git a/gcc/testsuite/g++.dg/modules/string-view1.C b/gcc/testsuite/g++.dg/modules/string-view1.C
new file mode 100644
index 00000000000..dabc16a8b01
--- /dev/null
+++ b/gcc/testsuite/g++.dg/modules/string-view1.C
@@ -0,0 +1,6 @@
+// { dg-additional-options "-fmodules-ts" }
+module;
+#include <cstdio>
+#include <string_view>
+export module foo;
+
diff --git a/gcc/testsuite/g++.dg/modules/string-view2.C b/gcc/testsuite/g++.dg/modules/string-view2.C
new file mode 100644
index 00000000000..2e389eacd8f
--- /dev/null
+++ b/gcc/testsuite/g++.dg/modules/string-view2.C
@@ -0,0 +1,53 @@
+// { dg-additional-options "-fmodules-ts" }
+// reduced from string-view1 through cvise. Broken under c++2a too.
+namespace std {
+typedef int a;
+int b;
+decltype(nullptr) c;
+namespace xyz {}
+__builtin_va_list d;
+int n;
+int e;
+int f;
+int g;
+int h;
+int i;
+int j;
+int k;
+typedef struct l m;
+typedef struct aa w;
+typedef struct x o;
+typedef x p;
+long q;
+long r;
+typedef l s;
+extern p ab;
+void t();
+void v();
+extern p ac;
+void ad();
+int ae;
+int af;
+extern p ag;
+extern p ah;
+void ai();
+void y();
+int aj;
+int ak;
+int al;
+char am;
+int an;
+a ao;
+int ap;
+int aq;
+void z();
+int ar;
+int as;
+void at();
+void au();
+void av();
+void aw();
+int u;
+namespace zz {
+}
+}
--
2.27.0
