Fix qualified name lookup for Rust

In https://github.com/rust-lang/rust/pull/46457, "m4b" pointed out
that the Rust support in gdb doesn't properly handle the lookup of
qualified names.

In particular, as shown in the test case in this patch, something like
"::NAME" should be found in the global scope, but is not.

This turns out to happen because rust_lookup_symbol_nonlocal does not
search the global scope unless the name in question is unqualified.
However, lookup_symbol_aux does not search the global scope, and
appears to search the static scope only as a fallback (I wonder if
this is needed?).

This patch fixes the problem by changing rust_lookup_symbol_nonlocal
to search the static and global blocks in more cases.

Regression tested against various versions of the rust compiler on
Fedora 26 x86-64.  (Note that there are unrelated failures with newer
versions of rustc; I will be addressing those separately.)

2018-01-19  Tom Tromey  <tom@tromey.com>

	* rust-lang.c (rust_lookup_symbol_nonlocal): Look up qualified
	symbols in the static and global blocks.

2018-01-19  Tom Tromey  <tom@tromey.com>

	* gdb.rust/modules.rs (TWENTY_THREE): New global.
	* gdb.rust/modules.exp: Add ::-qualified lookup test.
This commit is contained in:
Tom Tromey 2018-01-19 15:25:19 -07:00
parent 634c1c3109
commit fcfcc37696
5 changed files with 30 additions and 6 deletions

View File

@ -1,3 +1,8 @@
2018-01-19 Tom Tromey <tom@tromey.com>
* rust-lang.c (rust_lookup_symbol_nonlocal): Look up qualified
symbols in the static and global blocks.
2018-01-19 James Clarke <jrtc27@jrtc27.com>
* nat/linux-ptrace.c: Remove unnecessary reinclusion of

View File

@ -2201,19 +2201,25 @@ rust_lookup_symbol_nonlocal (const struct language_defn *langdef,
}
/* Look up bare names in the block's scope. */
std::string scopedname;
if (name[cp_find_first_component (name)] == '\0')
{
const char *scope = block_scope (block);
if (scope[0] != '\0')
{
std::string scopedname = std::string (scope) + "::" + name;
result = lookup_symbol_in_static_block (scopedname.c_str (), block,
domain);
if (result.symbol == NULL)
result = lookup_global_symbol (scopedname.c_str (), block, domain);
scopedname = std::string (scope) + "::" + name;
name = scopedname.c_str ();
}
else
name = NULL;
}
if (name != NULL)
{
result = lookup_symbol_in_static_block (name, block, domain);
if (result.symbol == NULL)
result = lookup_global_symbol (name, block, domain);
}
return result;
}

View File

@ -1,3 +1,8 @@
2018-01-19 Tom Tromey <tom@tromey.com>
* gdb.rust/modules.rs (TWENTY_THREE): New global.
* gdb.rust/modules.exp: Add ::-qualified lookup test.
2018-01-19 Andreas Arnez <arnez@linux.vnet.ibm.com>
* gdb.arch/s390-vregs.exp: Explicitly cast the return values of

View File

@ -89,3 +89,5 @@ foreach mod {mod1::inner::innest mod1::inner mod1 {}} {
gdb_breakpoint modules::${mod}f2 message
gdb_breakpoint "*::${mod}f2" message
}
gdb_test "print ::TWENTY_THREE" " = 23"

View File

@ -21,6 +21,10 @@ fn f2() {
println!("::f2");
}
// See https://github.com/rust-lang/rust/pull/46457
#[no_mangle]
pub static TWENTY_THREE : u16 = 23;
pub struct Generic<T>(T);
pub struct Type;
@ -56,6 +60,8 @@ pub mod mod1 {
let f2 = || println!("lambda f2");
let copy = ::TWENTY_THREE;
f2(); // set breakpoint here
f3();
self::f2();