From 1324b95f574f86018e947e1c5255a26266e0eefc Mon Sep 17 00:00:00 2001 From: =?utf8?q?Marek=20Piku=C5=82a?= Date: Wed, 28 May 2025 13:54:47 +0200 Subject: [PATCH] gdb/risc-v: fix ISA string detection for disassembly Commit 3f61a38 introduced a regression where the ISA string was no longer detected based on the ELF header. The mechanism was changed from directly referencing `abfd` to using `disassembler_info->section`, which was not properly initialized for RISC-V. The previous implementation ignored the object in scope, leading to issues such as failing to decode RVV instructions when a library was compiled as `rv64gcv` and the main application as `rv64gc`. This patch resolves both problems by initializing `disassembler_info->section` with the object currently in scope, ensuring correct ISA string detection during disassembly. Approved-By: Andrew Burgess --- gdb/riscv-tdep.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/gdb/riscv-tdep.c b/gdb/riscv-tdep.c index 6d439b0032c..f5b85230e71 100644 --- a/gdb/riscv-tdep.c +++ b/gdb/riscv-tdep.c @@ -4163,6 +4163,20 @@ riscv_gnu_triplet_regexp (struct gdbarch *gdbarch) return "riscv(32|64)?"; } +/* Implement the "print_insn" gdbarch method. */ + +static int +riscv_print_insn (bfd_vma addr, struct disassemble_info *info) +{ + /* Initialize the BFD section to enable ISA string detection depending on the + object in scope. */ + struct obj_section *s = find_pc_section (addr); + if (s != nullptr) + info->section = s->the_bfd_section; + + return default_print_insn (addr, info); +} + /* Implementation of `gdbarch_stap_is_single_operand', as defined in gdbarch.h. */ @@ -4429,6 +4443,9 @@ riscv_gdbarch_init (struct gdbarch_info info, disassembler_options_riscv ()); set_gdbarch_disassembler_options (gdbarch, &riscv_disassembler_options); + /* Disassembler print_insn. */ + set_gdbarch_print_insn (gdbarch, riscv_print_insn); + /* SystemTap Support. */ set_gdbarch_stap_is_single_operand (gdbarch, riscv_stap_is_single_operand); set_gdbarch_stap_register_indirection_prefixes -- 2.47.2