https://gcc.gnu.org/g:557cddcc71c9025932b30f1f825dc600a82dfe03
commit r14-10239-g557cddcc71c9025932b30f1f825dc600a82dfe03
Author: Nathaniel Shead <nathanielosh...@gmail.com>
Date: Sun Apr 14 23:03:11 2024 +1000
c++: Standardise errors for module_may_redeclare
Currently different places calling 'module_may_redeclare' all emit very
similar but slightly different error messages, and handle different
kinds of declarations differently. This patch makes the function
perform its own error messages so that they're all in one place, and
prepares it for use with temploid friends.
gcc/cp/ChangeLog:
* cp-tree.h (module_may_redeclare): Add default parameter.
* decl.cc (duplicate_decls): Don't emit errors for failed
module_may_redeclare.
(xref_tag): Likewise.
(start_enum): Likewise.
* semantics.cc (begin_class_definition): Likewise.
* module.cc (module_may_redeclare): Clean up logic. Emit error
messages on failure.
gcc/testsuite/ChangeLog:
* g++.dg/modules/enum-12.C: Update error message.
* g++.dg/modules/friend-5_b.C: Likewise.
* g++.dg/modules/shadow-1_b.C: Likewise.
Signed-off-by: Nathaniel Shead <nathanielosh...@gmail.com>
Reviewed-by: Jason Merrill <ja...@redhat.com>
(cherry picked from commit 2faf040335f9b49c33ba6d40cf317920f27ce431)
Diff:
---
gcc/cp/cp-tree.h | 2 +-
gcc/cp/decl.cc | 28 +------
gcc/cp/module.cc | 120 ++++++++++++++++++++----------
gcc/cp/semantics.cc | 6 +-
gcc/testsuite/g++.dg/modules/enum-12.C | 2 +-
gcc/testsuite/g++.dg/modules/friend-5_b.C | 2 +-
gcc/testsuite/g++.dg/modules/shadow-1_b.C | 5 +-
7 files changed, 89 insertions(+), 76 deletions(-)
diff --git a/gcc/cp/cp-tree.h b/gcc/cp/cp-tree.h
index 64760a40215..d4a70807460 100644
--- a/gcc/cp/cp-tree.h
+++ b/gcc/cp/cp-tree.h
@@ -7402,7 +7402,7 @@ inline bool module_exporting_p ()
extern module_state *get_module (tree name, module_state *parent = NULL,
bool partition = false);
-extern bool module_may_redeclare (tree decl);
+extern bool module_may_redeclare (tree olddecl, tree newdecl = NULL);
extern bool module_global_init_needed ();
extern bool module_determine_import_inits ();
diff --git a/gcc/cp/decl.cc b/gcc/cp/decl.cc
index fea66e838ce..93f81e42127 100644
--- a/gcc/cp/decl.cc
+++ b/gcc/cp/decl.cc
@@ -2279,18 +2279,8 @@ duplicate_decls (tree newdecl, tree olddecl, bool
hiding, bool was_hidden)
&& TREE_CODE (olddecl) != NAMESPACE_DECL
&& !hiding)
{
- if (!module_may_redeclare (olddecl))
- {
- if (DECL_ARTIFICIAL (olddecl))
- error ("declaration %qD conflicts with builtin", newdecl);
- else
- {
- error ("declaration %qD conflicts with import", newdecl);
- inform (olddecl_loc, "import declared %q#D here", olddecl);
- }
-
- return error_mark_node;
- }
+ if (!module_may_redeclare (olddecl, newdecl))
+ return error_mark_node;
tree not_tmpl = STRIP_TEMPLATE (olddecl);
if (DECL_LANG_SPECIFIC (not_tmpl)
@@ -16633,12 +16623,7 @@ xref_tag (enum tag_types tag_code, tree name,
{
tree decl = TYPE_NAME (t);
if (!module_may_redeclare (decl))
- {
- auto_diagnostic_group d;
- error ("cannot declare %qD in a different module", decl);
- inform (DECL_SOURCE_LOCATION (decl), "previously declared here");
- return error_mark_node;
- }
+ return error_mark_node;
tree not_tmpl = STRIP_TEMPLATE (decl);
if (DECL_LANG_SPECIFIC (not_tmpl)
@@ -16986,12 +16971,7 @@ start_enum (tree name, tree enumtype, tree
underlying_type,
{
tree decl = TYPE_NAME (enumtype);
if (!module_may_redeclare (decl))
- {
- auto_diagnostic_group d;
- error ("cannot declare %qD in different module", decl);
- inform (DECL_SOURCE_LOCATION (decl), "previously declared here");
- enumtype = error_mark_node;
- }
+ enumtype = error_mark_node;
else
set_instantiating_module (decl);
}
diff --git a/gcc/cp/module.cc b/gcc/cp/module.cc
index 3bf863e15d4..c2f077d6fd8 100644
--- a/gcc/cp/module.cc
+++ b/gcc/cp/module.cc
@@ -19003,11 +19003,15 @@ get_importing_module (tree decl, bool flexible)
return module->mod;
}
-/* Is it permissible to redeclare DECL. */
+/* Is it permissible to redeclare OLDDECL with NEWDECL.
+
+ If NEWDECL is NULL, assumes that OLDDECL will be redeclared using
+ the current scope's module and attachment. */
bool
-module_may_redeclare (tree decl)
+module_may_redeclare (tree olddecl, tree newdecl)
{
+ tree decl = olddecl;
for (;;)
{
tree ctx = CP_DECL_CONTEXT (decl);
@@ -19021,58 +19025,94 @@ module_may_redeclare (tree decl)
decl = TYPE_NAME (ctx);
}
- tree not_tmpl = STRIP_TEMPLATE (decl);
-
int use_tpl = 0;
- if (node_template_info (not_tmpl, use_tpl) && use_tpl)
+ if (node_template_info (STRIP_TEMPLATE (decl), use_tpl) && use_tpl)
// Specializations of any kind can be redeclared anywhere.
// FIXME: Should we be checking this in more places on the scope chain?
return true;
- if (!DECL_LANG_SPECIFIC (not_tmpl) || !DECL_MODULE_ATTACH_P (not_tmpl))
- // Decl is attached to global module. Current scope needs to be too.
- return !module_attach_p ();
+ module_state *old_mod = (*modules)[0];
+ module_state *new_mod = old_mod;
- module_state *me = (*modules)[0];
- module_state *them = me;
+ tree old_origin = get_originating_module_decl (decl);
+ tree old_inner = STRIP_TEMPLATE (old_origin);
+ bool olddecl_attached_p = (DECL_LANG_SPECIFIC (old_inner)
+ && DECL_MODULE_ATTACH_P (old_inner));
+ if (DECL_LANG_SPECIFIC (old_inner) && DECL_MODULE_IMPORT_P (old_inner))
+ {
+ unsigned index = import_entity_index (old_origin);
+ old_mod = import_entity_module (index);
+ }
- if (DECL_LANG_SPECIFIC (not_tmpl) && DECL_MODULE_IMPORT_P (not_tmpl))
+ bool newdecl_attached_p = module_attach_p ();
+ if (newdecl)
{
- /* We can be given the TEMPLATE_RESULT. We want the
- TEMPLATE_DECL. */
- int use_tpl = -1;
- if (tree ti = node_template_info (decl, use_tpl))
+ tree new_origin = get_originating_module_decl (newdecl);
+ tree new_inner = STRIP_TEMPLATE (new_origin);
+ newdecl_attached_p = (DECL_LANG_SPECIFIC (new_inner)
+ && DECL_MODULE_ATTACH_P (new_inner));
+ if (DECL_LANG_SPECIFIC (new_inner) && DECL_MODULE_IMPORT_P (new_inner))
{
- tree tmpl = TI_TEMPLATE (ti);
- if (use_tpl == 2)
- {
- /* A partial specialization. Find that specialization's
- template_decl. */
- for (tree list = DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
- list; list = TREE_CHAIN (list))
- if (DECL_TEMPLATE_RESULT (TREE_VALUE (list)) == decl)
- {
- decl = TREE_VALUE (list);
- break;
- }
- }
- else if (DECL_TEMPLATE_RESULT (tmpl) == decl)
- decl = tmpl;
+ unsigned index = import_entity_index (new_origin);
+ new_mod = import_entity_module (index);
}
- unsigned index = import_entity_index (decl);
- them = import_entity_module (index);
}
- // Decl is attached to named module. Current scope needs to be
- // attaching to the same module.
- if (!module_attach_p ())
- return false;
+ /* Module attachment needs to match. */
+ if (olddecl_attached_p == newdecl_attached_p)
+ {
+ if (!olddecl_attached_p)
+ /* Both are GM entities, OK. */
+ return true;
- // Both attached to named module.
- if (me == them)
- return true;
+ if (new_mod == old_mod
+ || (new_mod && get_primary (new_mod) == get_primary (old_mod)))
+ /* Both attached to same named module, OK. */
+ return true;
+ }
+
+ /* Attached to different modules, error. */
+ decl = newdecl ? newdecl : olddecl;
+ location_t loc = newdecl ? DECL_SOURCE_LOCATION (newdecl) : input_location;
+ if (DECL_IS_UNDECLARED_BUILTIN (olddecl))
+ error_at (loc, "declaration %qD conflicts with builtin", decl);
+ else if (DECL_LANG_SPECIFIC (old_inner) && DECL_MODULE_IMPORT_P (old_inner))
+ {
+ auto_diagnostic_group d;
+ if (newdecl_attached_p)
+ error_at (loc, "redeclaring %qD in module %qs conflicts with import",
+ decl, new_mod->get_flatname ());
+ else
+ error_at (loc, "redeclaring %qD in global module conflicts with import",
+ decl);
- return me && get_primary (them) == get_primary (me);
+ if (olddecl_attached_p)
+ inform (DECL_SOURCE_LOCATION (olddecl),
+ "import declared attached to module %qs",
+ old_mod->get_flatname ());
+ else
+ inform (DECL_SOURCE_LOCATION (olddecl),
+ "import declared in global module");
+ }
+ else
+ {
+ auto_diagnostic_group d;
+ if (newdecl_attached_p)
+ error_at (loc, "conflicting declaration of %qD in module %qs",
+ decl, new_mod->get_flatname ());
+ else
+ error_at (loc, "conflicting declaration of %qD in global module",
+ decl);
+
+ if (olddecl_attached_p)
+ inform (DECL_SOURCE_LOCATION (olddecl),
+ "previously declared in module %qs",
+ old_mod->get_flatname ());
+ else
+ inform (DECL_SOURCE_LOCATION (olddecl),
+ "previously declared in global module");
+ }
+ return false;
}
/* DECL is being created by this TU. Record it came from here. We
diff --git a/gcc/cp/semantics.cc b/gcc/cp/semantics.cc
index 4eeec209fa4..4513066d2ed 100644
--- a/gcc/cp/semantics.cc
+++ b/gcc/cp/semantics.cc
@@ -3779,11 +3779,7 @@ begin_class_definition (tree t)
if (modules_p ())
{
if (!module_may_redeclare (TYPE_NAME (t)))
- {
- error ("cannot declare %qD in a different module", TYPE_NAME (t));
- inform (DECL_SOURCE_LOCATION (TYPE_NAME (t)), "declared here");
- return error_mark_node;
- }
+ return error_mark_node;
set_instantiating_module (TYPE_NAME (t));
set_defining_module (TYPE_NAME (t));
}
diff --git a/gcc/testsuite/g++.dg/modules/enum-12.C
b/gcc/testsuite/g++.dg/modules/enum-12.C
index 57eeb85d92a..064f220dedf 100644
--- a/gcc/testsuite/g++.dg/modules/enum-12.C
+++ b/gcc/testsuite/g++.dg/modules/enum-12.C
@@ -4,7 +4,7 @@
export module foo;
namespace std {
- enum class align_val_t : decltype(sizeof(int)) {}; // { dg-error "different
module" }
+ enum class align_val_t : decltype(sizeof(int)) {}; // { dg-error "conflicts
with builtin" }
}
// { dg-prune-output "not writing module" }
diff --git a/gcc/testsuite/g++.dg/modules/friend-5_b.C
b/gcc/testsuite/g++.dg/modules/friend-5_b.C
index f043d7a340d..6b561265155 100644
--- a/gcc/testsuite/g++.dg/modules/friend-5_b.C
+++ b/gcc/testsuite/g++.dg/modules/friend-5_b.C
@@ -4,7 +4,7 @@
export module bar;
import foo;
-class B { // { dg-error "in a different module" }
+class B { // { dg-error "conflicts with import" }
B() { object.value = 42; }
A object;
};
diff --git a/gcc/testsuite/g++.dg/modules/shadow-1_b.C
b/gcc/testsuite/g++.dg/modules/shadow-1_b.C
index 646381237ac..7f6a3182998 100644
--- a/gcc/testsuite/g++.dg/modules/shadow-1_b.C
+++ b/gcc/testsuite/g++.dg/modules/shadow-1_b.C
@@ -1,8 +1,5 @@
// { dg-additional-options -fmodules-ts }
import shadow;
-// unfortunately not the exact same diagnostic in both cases :(
-
void stat (); // { dg-error "conflicts with import" }
-
-struct stat {}; // { dg-error "in a different module" }
+struct stat {}; // { dg-error "conflicts with import" }
