https://gcc.gnu.org/bugzilla/show_bug.cgi?id=125787
Bug ID: 125787
Summary: [modules] Including headers and using modules with
-freflection enabled causes conflicting imported
declarations
Product: gcc
Version: 16.1.1
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: keipitalists at proton dot me
Target Milestone: ---
Created attachment 64736
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=64736&action=edit
Compilation error output + gcc -v output
If a module includes certain headers with typedef'd structures in the global
module fragment, and is imported from a file that also includes the same
headers, compilation fails due to conflicting declarations, when compiled with
-freflection.
Example:
//my_module.cpp
module;
#include <string>
export module my_module;
std::string my_function();
//a.cpp
#include <string>
import my_module;
Compilation fails with: g++ -fmodules-ts -freflection -c -std=c++26
./my_module.cpp ./a.cpp
Compilation succeeds with: g++ -fmodules-ts -c -std=c++26 ./my_module.cpp
./a.cpp
