From fcfcc376969c4d7a6d20827c47b584db389a32b9 Mon Sep 17 00:00:00 2001 From: Tom Tromey Date: Fri, 19 Jan 2018 15:25:19 -0700 Subject: [PATCH] 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 * rust-lang.c (rust_lookup_symbol_nonlocal): Look up qualified symbols in the static and global blocks. 2018-01-19 Tom Tromey * gdb.rust/modules.rs (TWENTY_THREE): New global. * gdb.rust/modules.exp: Add ::-qualified lookup test. --- gdb/ChangeLog | 5 +++++ gdb/rust-lang.c | 18 ++++++++++++------ gdb/testsuite/ChangeLog | 5 +++++ gdb/testsuite/gdb.rust/modules.exp | 2 ++ gdb/testsuite/gdb.rust/modules.rs | 6 ++++++ 5 files changed, 30 insertions(+), 6 deletions(-) diff --git a/gdb/ChangeLog b/gdb/ChangeLog index e274caa..d2d4472 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,8 @@ +2018-01-19 Tom Tromey + + * rust-lang.c (rust_lookup_symbol_nonlocal): Look up qualified + symbols in the static and global blocks. + 2018-01-19 James Clarke * nat/linux-ptrace.c: Remove unnecessary reinclusion of diff --git a/gdb/rust-lang.c b/gdb/rust-lang.c index f7bec33..5ff80b2 100644 --- a/gdb/rust-lang.c +++ b/gdb/rust-lang.c @@ -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; } diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog index 36c4924..2b96801 100644 --- a/gdb/testsuite/ChangeLog +++ b/gdb/testsuite/ChangeLog @@ -1,3 +1,8 @@ +2018-01-19 Tom Tromey + + * gdb.rust/modules.rs (TWENTY_THREE): New global. + * gdb.rust/modules.exp: Add ::-qualified lookup test. + 2018-01-19 Andreas Arnez * gdb.arch/s390-vregs.exp: Explicitly cast the return values of diff --git a/gdb/testsuite/gdb.rust/modules.exp b/gdb/testsuite/gdb.rust/modules.exp index ced2eb8..6a50e9f 100644 --- a/gdb/testsuite/gdb.rust/modules.exp +++ b/gdb/testsuite/gdb.rust/modules.exp @@ -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" diff --git a/gdb/testsuite/gdb.rust/modules.rs b/gdb/testsuite/gdb.rust/modules.rs index e005865..3ba1253 100644 --- a/gdb/testsuite/gdb.rust/modules.rs +++ b/gdb/testsuite/gdb.rust/modules.rs @@ -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); 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(); -- 2.7.4