Worked on the rust-lang/gcc repository to address a critical issue in RISC-V code generation, focusing on compiler development and optimization. Implemented a fix in C++ and Assembly that suppresses cross-calling-convention tail call optimization when a function using the vector calling convention invokes a non-vector function, preventing register corruption. Added targeted tests to ensure correctness and guard against future regressions in mixed vector and non-vector call scenarios. This change improved the reliability and portability of code generation for RISC-V architectures, reducing the risk of subtle bugs in cross-architecture builds and enhancing the stability of production environments using these calling conventions.