From: Tom Tromey <tom@tromey.com>
To: gdb-patches@sourceware.org
Cc: Tom Tromey <tom@tromey.com>
Subject: [PATCH] Use rust_demangle to fix a crash
Date: Sun, 19 Mar 2023 09:35:06 -0600 [thread overview]
Message-ID: <20230319153506.3382669-1-tom@tromey.com> (raw)
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
---
gdb/defs.h | 8 ++++----
gdb/rust-lang.h | 4 ++--
gdb/testsuite/gdb.rust/methods.exp | 3 +++
3 files changed, 9 insertions(+), 6 deletions(-)
diff --git a/gdb/defs.h b/gdb/defs.h
index 90748c586f4..a83171e92b9 100644
--- a/gdb/defs.h
+++ b/gdb/defs.h
@@ -204,9 +204,9 @@ 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). (Keep this order in sync
+ with the 'languages' array in language.c.) */
enum language
{
@@ -214,6 +214,7 @@ 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 +223,6 @@ 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 @@ class rust_language : public language_defn
(const char *mangled, gdb::unique_xmalloc_ptr<char> *demangled)
const override
{
- *demangled = gdb_demangle (mangled, DMGL_PARAMS | DMGL_ANSI);
+ demangled->reset (rust_demangle (mangled, 0));
return *demangled != NULL;
}
@@ -102,7 +102,7 @@ class rust_language : public language_defn
gdb::unique_xmalloc_ptr<char> demangle_symbol (const char *mangled,
int options) const override
{
- return gdb_demangle (mangled, options);
+ return gdb::unique_xmalloc_ptr<char> (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"
--
2.39.1
next reply other threads:[~2023-03-19 15:35 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-03-19 15:35 Tom Tromey [this message]
2023-03-20 9:53 ` Andrew Burgess
2023-03-20 13:48 ` Tom Tromey
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