https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112912
Bug ID: 112912 Summary: How to implement a mangle interface in c Product: gcc Version: 12.2.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c Assignee: unassigned at gcc dot gnu.org Reporter: mark_wang1234 at 163 dot com Target Milestone: --- Clang implements kcfi for low-level system software to support forward-edge cfi. clang kcfi uses the mangled-name defined in Itanium c++ ABI as input to generate cfi type id, and uses the xxhash algorithm to generate cfi type id. Dan Li implemented a forward-edge cfi scheme for gcc, but the algorithm for generating cfi type id in this scheme is different from clang kcfi. He designed a general cfi type id algorithm (incompatible with clang kcfi). I am Dan Li’s colleague, and I will continue to complete this work later. The following is the patch implemented by Dan Li to support forward-edge cfi in gcc: https://lore.kernel.org/lkml/20221219055431.22596-2-ashimida.1...@gmail.com/raw https://lore.kernel.org/lkml/20221219055431.22596-3-ashimida.1...@gmail.com/raw https://lore.kernel.org/lkml/20221219055431.22596-4-ashimida.1...@gmail.com/raw I would like to implement a clang kcfi compatible CFI type id generation method based on his work: 1. For c++, use the existing mangle_typeinfo_string_for_type interface to generate the input string of the xxhash algorithm; 2. For c, refer to the implementation of gcc/cp/mangle.cc and implement the mangle_typeinfo_string_for_type interface in the gcc/c/ directory; Currently my solution has encountered the following two problems: 1. Can I implement a simple mangle interface in the gcc/c directory for generating cfi type id? Or should a unified mangle interface be provided for c and c++? Or do you have any other suggestions? 2. I want to call interfaces defined in different front-end languages under the interface defined by targetm. How should I implement this?