[lldb] Fix StdUnorderedMapSynthProvider for GCC (#164251) This patch adds small workaround for [issue](https://github.com/llvm/llvm-project/issues/152504). It looks like code compiled with gcc has lack of some important debug information (e.g. DW_TAG_template_type_parameter for allocator). Example code: ```cpp #include <unordered_map> int main() { std::unordered_map<int, int> map = { {1, 2} }; return 0; } ``` Output from `llvm-dwarfdump` for code compiled by GCC or Clang. I used system GCC (13.3.0) and Clang (18.1.3) on Ubuntu 24.04 (WSL). GCC: ``` 0x00001fcd: DW_TAG_class_type DW_AT_name ("allocator<std::pair<int const, int> >") DW_AT_byte_size (0x01) DW_AT_decl_file ("/usr/include/c++/13/bits/allocator.h") DW_AT_decl_line (130) DW_AT_decl_column (11) DW_AT_sibling (0x0000207c) 0x00001fda: DW_TAG_inheritance DW_AT_type (0x00001d0a "std::__new_allocator<std::pair<int const, int> >") DW_AT_data_member_location (0) DW_AT_accessibility (DW_ACCESS_public) 0x00001fe0: DW_TAG_subprogram DW_AT_external (true) DW_AT_name ("allocator") DW_AT_decl_file ("/usr/include/c++/13/bits/allocator.h") DW_AT_decl_line (163) DW_AT_decl_column (7) DW_AT_linkage_name ("_ZNSaISt4pairIKiiEEC4Ev") DW_AT_accessibility (DW_ACCESS_public) DW_AT_declaration (true) DW_AT_object_pointer (0x00001ff4) DW_AT_sibling (0x00001ffa) 0x00001ff4: DW_TAG_formal_parameter DW_AT_type (0x00004eb9 "std::allocator<std::pair<int const, int> > *") DW_AT_artificial (true) 0x00001ff9: NULL 0x00001ffa: DW_TAG_subprogram DW_AT_external (true) DW_AT_name ("allocator") DW_AT_decl_file ("/usr/include/c++/13/bits/allocator.h") DW_AT_decl_line (167) DW_AT_decl_column (7) DW_AT_linkage_name ("_ZNSaISt4pairIKiiEEC4ERKS2_") DW_AT_accessibility (DW_ACCESS_public) DW_AT_declaration (true) DW_AT_object_pointer (0x0000200e) DW_AT_sibling (0x00002019) 0x0000200e: DW_TAG_formal_parameter DW_AT_type (0x00004eb9 "std::allocator<std::pair<int const, int> > *") DW_AT_artificial (true) 0x00002013: DW_TAG_formal_parameter DW_AT_type (0x00004ec3 "const std::allocator<std::pair<int const, int> > &") 0x00002018: NULL 0x00002019: DW_TAG_subprogram DW_AT_external (true) DW_AT_name ("operator=") DW_AT_decl_file ("/usr/include/c++/13/bits/allocator.h") DW_AT_decl_line (172) DW_AT_decl_column (18) DW_AT_linkage_name ("_ZNSaISt4pairIKiiEEaSERKS2_") DW_AT_type (0x00004ec8 "std::allocator<std::pair<int const, int> > &") DW_AT_accessibility (DW_ACCESS_public) DW_AT_declaration (true) DW_AT_defaulted (DW_DEFAULTED_in_class) DW_AT_object_pointer (0x00002031) DW_AT_sibling (0x0000203c) 0x00002031: DW_TAG_formal_parameter DW_AT_type (0x00004eb9 "std::allocator<std::pair<int const, int> > *") DW_AT_artificial (true) 0x00002036: DW_TAG_formal_parameter DW_AT_type (0x00004ec3 "const std::allocator<std::pair<int const, int> > &") 0x0000203b: NULL 0x0000203c: DW_TAG_subprogram DW_AT_external (true) DW_AT_name ("~allocator") DW_AT_decl_file ("/usr/include/c++/13/bits/allocator.h") DW_AT_decl_line (184) DW_AT_decl_column (7) DW_AT_linkage_name ("_ZNSaISt4pairIKiiEED4Ev") DW_AT_accessibility (DW_ACCESS_public) DW_AT_declaration (true) DW_AT_object_pointer (0x00002050) DW_AT_sibling (0x0000205b) 0x00002050: DW_TAG_formal_parameter DW_AT_type (0x00004eb9 "std::allocator<std::pair<int const, int> > *") DW_AT_artificial (true) 0x00002055: DW_TAG_formal_parameter DW_AT_type (0x00004cab "int") DW_AT_artificial (true) 0x0000205a: NULL ``` Clang: ``` 0x00001a6e: DW_TAG_class_type DW_AT_calling_convention (DW_CC_pass_by_reference) DW_AT_name ("allocator<std::pair<const int, int> >") DW_AT_byte_size (0x01) DW_AT_decl_file ("/usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/bits/allocator.h") DW_AT_decl_line (130) 0x00001a74: DW_TAG_template_type_parameter DW_AT_type (0x00000dec "std::pair<const int, int>") DW_AT_name ("_Tp") 0x00001a7a: DW_TAG_inheritance DW_AT_type (0x00001ad5 "std::__allocator_base<std::pair<const int, int> >") DW_AT_data_member_location (0x00) DW_AT_accessibility (DW_ACCESS_public) 0x00001a81: DW_TAG_subprogram DW_AT_name ("allocator") DW_AT_decl_file ("/usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/bits/allocator.h") DW_AT_decl_line (163) DW_AT_declaration (true) DW_AT_external (true) DW_AT_accessibility (DW_ACCESS_public) 0x00001a86: DW_TAG_formal_parameter DW_AT_type (0x00002dd1 "std::allocator<std::pair<const int, int> > *") DW_AT_artificial (true) 0x00001a8b: NULL 0x00001a8c: DW_TAG_subprogram DW_AT_name ("allocator") DW_AT_decl_file ("/usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/bits/allocator.h") DW_AT_decl_line (167) DW_AT_declaration (true) DW_AT_external (true) DW_AT_accessibility (DW_ACCESS_public) 0x00001a91: DW_TAG_formal_parameter DW_AT_type (0x00002dd1 "std::allocator<std::pair<const int, int> > *") DW_AT_artificial (true) 0x00001a96: DW_TAG_formal_parameter DW_AT_type (0x00002dd6 "const std::allocator<std::pair<const int, int> > &") 0x00001a9b: NULL 0x00001a9c: DW_TAG_subprogram DW_AT_linkage_name ("_ZNSaISt4pairIKiiEEaSERKS2_") DW_AT_name ("operator=") DW_AT_decl_file ("/usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/bits/allocator.h") DW_AT_decl_line (172) DW_AT_type (0x00002de0 "std::allocator<std::pair<const int, int> > &") DW_AT_declaration (true) DW_AT_external (true) DW_AT_accessibility (DW_ACCESS_public) 0x00001aa6: DW_TAG_formal_parameter DW_AT_type (0x00002dd1 "std::allocator<std::pair<const int, int> > *") DW_AT_artificial (true) 0x00001aab: DW_TAG_formal_parameter DW_AT_type (0x00002dd6 "const std::allocator<std::pair<const int, int> > &") 0x00001ab0: NULL 0x00001ab1: DW_TAG_subprogram DW_AT_name ("~allocator") DW_AT_decl_file ("/usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/bits/allocator.h") DW_AT_decl_line (184) DW_AT_declaration (true) DW_AT_external (true) DW_AT_accessibility (DW_ACCESS_public) 0x00001ab6: DW_TAG_formal_parameter DW_AT_type (0x00002dd1 "std::allocator<std::pair<const int, int> > *") DW_AT_artificial (true) 0x00001abb: NULL ``` I propose to add fallback implementation based on type of `_M_h`.
Welcome to the LLVM project!
This repository contains the source code for LLVM, a toolkit for the construction of highly optimized compilers, optimizers, and run-time environments.
The LLVM project has multiple components. The core of the project is itself called “LLVM”. This contains all of the tools, libraries, and header files needed to process intermediate representations and convert them into object files. Tools include an assembler, disassembler, bitcode analyzer, and bitcode optimizer.
C-like languages use the Clang frontend. This component compiles C, C++, Objective-C, and Objective-C++ code into LLVM bitcode -- and from there into object files, using LLVM.
Other components include: the libc++ C++ standard library, the LLD linker, and more.
Consult the Getting Started with LLVM page for information on building and running LLVM.
For information on how to contribute to the LLVM project, please take a look at the Contributing to LLVM guide.
Join the LLVM Discourse forums, Discord chat, LLVM Office Hours or Regular sync-ups.
The LLVM project has adopted a code of conduct for participants to all modes of communication within the project.