From 43cc5389bc4662b31cad02a9f13358bd367d0ab3 Mon Sep 17 00:00:00 2001 From: Tom Tromey Date: Sun, 14 May 2017 11:12:14 -0600 Subject: Use watchpoint's language when re-parsing expression PR rust/21484 notes that watch -location does not work with Rust: (gdb) watch -location a syntax error in expression, near `) 0x00007fffffffe0f4'. update_watchpoint tries to tell gdb that the new expression it creates has C syntax: /* The above expression is in C. */ b->language = language_c; However, update_watchpoint doesn't actually use this language when re-parsing the expression. Originally I was going to fix this by saving and restoring the language in update_watchpoint, but this regressed gdb.dlang/watch-loc.exp, because the constructed expression actually has D syntax (specifically the name is not parseable by C). Next I looked at directly constructing an expression, and not relying on the parser at all; but it seemed to me that upon a re-set, we'd want to reparse the type, and there is no existing API to do this correctly. So, in the end I made a hook to let each language choose what expression to use. I made all the languages other than Rust use the C expression, because that is the status quo ante. However, this is probably not truly correct. After this patch, at least, it is easy to correct by someone who knows the language(s) in question. Regtested by the buildbot. ChangeLog 2017-05-19 Tom Tromey PR rust/21484: * rust-lang.c (exp_descriptor_rust): New function. (rust_language_defn): Use it. * p-lang.c (pascal_language_defn): Update. * opencl-lang.c (opencl_language_defn): Update. * objc-lang.c (objc_language_defn): Update. * m2-lang.c (m2_language_defn): Update. * language.h (struct language_defn) : New member. * language.c (unknown_language_defn, auto_language_defn) (local_language_defn): Update. * go-lang.c (go_language_defn): Update. * f-lang.c (f_language_defn): Update. * d-lang.c (d_language_defn): Update. * c-lang.h (c_watch_location_expression): Declare. * c-lang.c (c_watch_location_expression): New function. (c_language_defn, cplus_language_defn, asm_language_defn) (minimal_language_defn): Use it. * breakpoint.c (watch_command_1): Call la_watch_location_expression. * ada-lang.c (ada_language_defn): Update. testsuite/ChangeLog 2017-05-19 Tom Tromey PR rust/21484: * gdb.rust/watch.exp: New file. * gdb.rust/watch.rs: New file. --- gdb/language.h | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'gdb/language.h') diff --git a/gdb/language.h b/gdb/language.h index 58bcbe8..cc0df8c 100644 --- a/gdb/language.h +++ b/gdb/language.h @@ -358,6 +358,12 @@ struct language_defn void (*la_get_string) (struct value *value, gdb_byte **buffer, int *length, struct type **chartype, const char **charset); + /* Return an expression that can be used for a location + watchpoint. TYPE is a pointer type that points to the memory + to watch, and ADDR is the address of the watched memory. */ + gdb::unique_xmalloc_ptr (*la_watch_location_expression) + (struct type *type, CORE_ADDR addr); + /* Return a pointer to the function that should be used to match a symbol name against LOOKUP_NAME. This is mostly for languages such as Ada where the matching algorithm depends on LOOKUP_NAME. -- cgit v1.1