Darwin linker improves robustness in select_section.
Darwin's linker `select_section` handles NULL_TREE types gracefully.
The Darwin Mach-O PIC (Position Independent Code) section selection logic has been made more robust. It now gracefully handles cases where a NULL_TREE might be passed as a type name, preventing potential crashes or errors when inspecting Objective-C or CoreFoundation strings.
In Details
The machopic_select_section function in config/darwin.cc is updated to safely handle NULL_TREE type identifiers. This addresses a potential issue where a malformed type could be passed, which would have otherwise caused a crash when attempting to inspect it for Objective-C/CoreFoundation string initialization within constructors. The change improves the robustness of the Darwin backend's section selection logic.
- Mach-O
- The executable file format used by macOS, iOS, and other Apple operating systems. It's a universal binary format that can contain code for multiple processor architectures.
- PIC
- Position-Independent Code. Code that can run correctly regardless of where it is loaded in memory. This is essential for shared libraries.
- CONSTRUCTOR
- In C/C++, a function marked with an attribute (like
__attribute__((constructor))) that is executed automatically before themainfunction starts. It's often used for initialization. - NULL_TREE
- In GCC's internal representation, a null or invalid node in the abstract syntax tree (AST) or intermediate representation (IR). It signifies the absence of a valid tree structure.