From 6e7eef72164c00d6a5a7b0bce9fa01f5481f33cb Mon Sep 17 00:00:00 2001 From: Tom Tromey Date: Sun, 19 Mar 2023 09:13:10 -0600 Subject: [PATCH] Use rust_demangle to fix a crash PR rust/30211 points out a crash caused by a particular completion. This turns out to happen because a Rust minsym winds up in a C++-specific path in strncmp_iw_with_mode, which ultimately causes the completer to pass invalid arguments to string::append. This patch fixes the bug by reordering the language constants so that Rust comes before C++, and then using rust_demangle. This ensures that minsyms are correctly marked as "Rust", avoiding this code and thus the crash. Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=20367 Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=30211 Reviewed-By: Andrew Burgess --- gdb/defs.h | 7 +++---- gdb/rust-lang.h | 4 ++-- gdb/testsuite/gdb.rust/methods.exp | 3 +++ 3 files changed, 8 insertions(+), 6 deletions(-) diff --git a/gdb/defs.h b/gdb/defs.h index 90748c586f4..8dbb68e440b 100644 --- a/gdb/defs.h +++ b/gdb/defs.h @@ -204,9 +204,8 @@ extern void quit_serial_event_clear (void); these languages, so some symbols could be successfully demangled by several languages. For that reason, the constants here are sorted in the order we'll attempt demangling them. For example: Rust uses - C++ mangling, so must come after C++; Ada must come last (see - ada_sniff_from_mangled_name). (Keep this order in sync with the - 'languages' array in language.c.) */ + a C++-compatible mangling, so must come before C++; Ada must come + last (see ada_sniff_from_mangled_name). */ enum language { @@ -214,6 +213,7 @@ enum language language_auto, /* Placeholder for automatic setting */ language_c, /* C */ language_objc, /* Objective-C */ + language_rust, /* Rust */ language_cplus, /* C++ */ language_d, /* D */ language_go, /* Go */ @@ -222,7 +222,6 @@ enum language language_asm, /* Assembly language */ language_pascal, /* Pascal */ language_opencl, /* OpenCL */ - language_rust, /* Rust */ language_minimal, /* All other languages, minimal support only */ language_ada, /* Ada */ nr_languages diff --git a/gdb/rust-lang.h b/gdb/rust-lang.h index 37a22e7a404..efe721c5707 100644 --- a/gdb/rust-lang.h +++ b/gdb/rust-lang.h @@ -93,7 +93,7 @@ public: (const char *mangled, gdb::unique_xmalloc_ptr *demangled) const override { - *demangled = gdb_demangle (mangled, DMGL_PARAMS | DMGL_ANSI); + demangled->reset (rust_demangle (mangled, 0)); return *demangled != NULL; } @@ -102,7 +102,7 @@ public: gdb::unique_xmalloc_ptr demangle_symbol (const char *mangled, int options) const override { - return gdb_demangle (mangled, options); + return gdb::unique_xmalloc_ptr (rust_demangle (mangled, options)); } /* See language.h. */ diff --git a/gdb/testsuite/gdb.rust/methods.exp b/gdb/testsuite/gdb.rust/methods.exp index 8374ab162ec..72be6a11ab0 100644 --- a/gdb/testsuite/gdb.rust/methods.exp +++ b/gdb/testsuite/gdb.rust/methods.exp @@ -59,3 +59,6 @@ gdb_test "print *self" " = 23" gdb_test "info functions HasMethods::new" \ "fn methods::HasMethods::new\\(\\) -> methods::HasMethods;" +# Regression test for PR rust/20367 and PR rust/30211. This used to +# crash. +gdb_test_no_output "complete break what" -- 2.30.2