[PATCH] c++/modules: Propagate BINDING_VECTOR_*_DUPS_P on realloc [PR99242]

[Nathaniel Shead]

Bootstrapped and regtested (so far just modules.exp) on
x86_64-pc-linux-gnu, OK for trunk/14 if full regtest succeeds?

-- >8 --

When importing modules, when a binding vector for a name runs out of
slots it gets reallocated with a larger size, and existing bindings are
copied across.  However, the flags to indicate whether deduping needs to
occur did not: this causes ICEs, as it allows a duplicate binding to be
added which then violates assumptions later on.

        PR c++/99242

gcc/cp/ChangeLog:

        * name-lookup.cc (append_imported_binding_slot): Propagate dups
        flags.

gcc/testsuite/ChangeLog:

        * g++.dg/modules/pr99242_a.H: New test.
        * g++.dg/modules/pr99242_b.H: New test.
        * g++.dg/modules/pr99242_c.H: New test.
        * g++.dg/modules/pr99242_d.C: New test.

Signed-off-by: Nathaniel Shead <nathanielosh...@gmail.com>
---
 gcc/cp/name-lookup.cc                    | 4 ++++
 gcc/testsuite/g++.dg/modules/pr99242_a.H | 3 +++
 gcc/testsuite/g++.dg/modules/pr99242_b.H | 3 +++
 gcc/testsuite/g++.dg/modules/pr99242_c.H | 3 +++
 gcc/testsuite/g++.dg/modules/pr99242_d.C | 7 +++++++
 5 files changed, 20 insertions(+)
 create mode 100644 gcc/testsuite/g++.dg/modules/pr99242_a.H
 create mode 100644 gcc/testsuite/g++.dg/modules/pr99242_b.H
 create mode 100644 gcc/testsuite/g++.dg/modules/pr99242_c.H
 create mode 100644 gcc/testsuite/g++.dg/modules/pr99242_d.C

diff --git a/gcc/cp/name-lookup.cc b/gcc/cp/name-lookup.cc
index b57893116eb..3f0b8a59ff4 100644
--- a/gcc/cp/name-lookup.cc
+++ b/gcc/cp/name-lookup.cc
@@ -352,6 +352,10 @@ append_imported_binding_slot (tree *slot, tree name, 
unsigned ix)
 
       tree new_vec = make_binding_vec (name, want);
       BINDING_VECTOR_NUM_CLUSTERS (new_vec) = have + 1;
+      BINDING_VECTOR_GLOBAL_DUPS_P (new_vec)
+       = BINDING_VECTOR_GLOBAL_DUPS_P (*slot);
+      BINDING_VECTOR_PARTITION_DUPS_P (new_vec)
+       = BINDING_VECTOR_PARTITION_DUPS_P (*slot);
       memcpy (BINDING_VECTOR_CLUSTER_BASE (new_vec),
              BINDING_VECTOR_CLUSTER_BASE (*slot),
              have * sizeof (binding_cluster));
diff --git a/gcc/testsuite/g++.dg/modules/pr99242_a.H 
b/gcc/testsuite/g++.dg/modules/pr99242_a.H
new file mode 100644
index 00000000000..2df0b4184ab
--- /dev/null
+++ b/gcc/testsuite/g++.dg/modules/pr99242_a.H
@@ -0,0 +1,3 @@
+// { dg-additional-options "-fmodule-header" }
+// { dg-module-cmi {} }
+bool __is_constant_evaluated();
diff --git a/gcc/testsuite/g++.dg/modules/pr99242_b.H 
b/gcc/testsuite/g++.dg/modules/pr99242_b.H
new file mode 100644
index 00000000000..2df0b4184ab
--- /dev/null
+++ b/gcc/testsuite/g++.dg/modules/pr99242_b.H
@@ -0,0 +1,3 @@
+// { dg-additional-options "-fmodule-header" }
+// { dg-module-cmi {} }
+bool __is_constant_evaluated();
diff --git a/gcc/testsuite/g++.dg/modules/pr99242_c.H 
b/gcc/testsuite/g++.dg/modules/pr99242_c.H
new file mode 100644
index 00000000000..2df0b4184ab
--- /dev/null
+++ b/gcc/testsuite/g++.dg/modules/pr99242_c.H
@@ -0,0 +1,3 @@
+// { dg-additional-options "-fmodule-header" }
+// { dg-module-cmi {} }
+bool __is_constant_evaluated();
diff --git a/gcc/testsuite/g++.dg/modules/pr99242_d.C 
b/gcc/testsuite/g++.dg/modules/pr99242_d.C
new file mode 100644
index 00000000000..1046d1af984
--- /dev/null
+++ b/gcc/testsuite/g++.dg/modules/pr99242_d.C
@@ -0,0 +1,7 @@
+// { dg-additional-options "-fmodules-ts" }
+bool __is_constant_evaluated();
+import "pr99242_a.H";
+void f() { __is_constant_evaluated(); }
+import "pr99242_b.H";
+import "pr99242_c.H";
+void g() { __is_constant_evaluated(); }
-- 
2.43.2