https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110447
Bug ID: 110447
Summary: [modules] unexpected attachment of GMF decls to a
named module.
Product: gcc
Version: 14.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: iains at gcc dot gnu.org
Target Milestone: ---
While trying to compare behaviour of GCC and clang ....
====
Foo.cpp:
module;
#include <iostream>
export module Foo;
export void
my_hello (const char *str)
{
std::cout << str << std::endl;
}
====
pr61465.cpp:
import Foo; // assume module 'foo' contain the declarations from `<iostream>`
#include <iostream>
int main(int argc, char *argv[])
{
std::cout << "Test\n";
my_hello ("and we used Foo");
return 0;
}
====
g++ -std=c++20 -fmodules-ts Foo.cpp -c
g++ -std=c++20 -fmodules-ts pr6145-main.cpp Foo.o -o t -flang-info-module-cmi
...
In module imported at pr6145-main.cpp:1:1:
Foo: note: reading CMI ‘gcm.cache/Foo.gcm’
<snip include stack traceback>
/usr/include/runetype.h:111:20: error: conflicting declaration ‘_RuneLocale
_DefaultRuneLocale’
<snip include stack traceback>
/usr/include/runetype.h:111:20: note: previous declaration as ‘_RuneLocale@Foo
_DefaultRuneLocale@Foo’
====
NOTE: iostream is _not_ built as a header unit in this case (if we do that the
problem disappears).
----
What seems wrong here is that the _RuneLocale symbol appears to be attached to
Foo - but ir should be part of the GMF of Foo and not visible to importers
(although potentially reachable if used in the module purview of Foo).
unless i miss something?
