From b3e3859bc577db5b79bb3d39048fd46c0a0420ef Mon Sep 17 00:00:00 2001 From: Tom Tromey Date: Mon, 2 Oct 2017 13:47:15 -0600 Subject: [PATCH] Fix ptype of Rust slices Something like "ptype &x[..]" (where "x" was a slice) would crash gdb. rust_subscript wasn't handling slicing in the EVAL_AVOID_SIDE_EFFECTS case. 2017-10-02 Tom Tromey * rust-lang.c (rust_subscript): Handle slices in EVAL_AVOID_SIDE_EFFECTS case. 2017-10-02 Tom Tromey * gdb.rust/simple.exp: Test ptype of a slice. --- gdb/ChangeLog | 5 ++++ gdb/rust-lang.c | 42 ++++++++++++++++++++++++++++--- gdb/testsuite/ChangeLog | 4 +++ gdb/testsuite/gdb.rust/simple.exp | 19 ++++++++++++++ 4 files changed, 67 insertions(+), 3 deletions(-) diff --git a/gdb/ChangeLog b/gdb/ChangeLog index a8820c8abb..11c1ca374e 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,8 @@ +2017-10-02 Tom Tromey + + * rust-lang.c (rust_subscript): Handle slices in + EVAL_AVOID_SIDE_EFFECTS case. + 2017-10-02 Tom Tromey * rust-lang.c (rust_slice_type_p): Recognize &str as a slice type. diff --git a/gdb/rust-lang.c b/gdb/rust-lang.c index a9895feaf1..9b64efad78 100644 --- a/gdb/rust-lang.c +++ b/gdb/rust-lang.c @@ -1456,17 +1456,53 @@ rust_subscript (struct expression *exp, int *pos, enum noside noside, else low = value_as_long (rhs); + struct type *type = check_typedef (value_type (lhs)); if (noside == EVAL_AVOID_SIDE_EFFECTS) { - struct type *type = check_typedef (value_type (lhs)); + struct type *base_type = nullptr; + if (TYPE_CODE (type) == TYPE_CODE_ARRAY) + base_type = TYPE_TARGET_TYPE (type); + else if (rust_slice_type_p (type)) + { + for (int i = 0; i < TYPE_NFIELDS (type); ++i) + { + if (strcmp (TYPE_FIELD_NAME (type, i), "data_ptr") == 0) + { + base_type = TYPE_TARGET_TYPE (TYPE_FIELD_TYPE (type, i)); + break; + } + } + if (base_type == nullptr) + error (_("Could not find 'data_ptr' in slice type")); + } + else if (TYPE_CODE (type) == TYPE_CODE_PTR) + base_type = TYPE_TARGET_TYPE (type); + else + error (_("Cannot subscript non-array type")); + + struct type *new_type; + if (want_slice) + { + if (rust_slice_type_p (type)) + new_type = type; + else + { + struct type *usize + = language_lookup_primitive_type (exp->language_defn, + exp->gdbarch, + "usize"); + new_type = rust_slice_type ("&[*gdb*]", base_type, usize); + } + } + else + new_type = base_type; - result = value_zero (TYPE_TARGET_TYPE (type), VALUE_LVAL (lhs)); + return value_zero (new_type, VALUE_LVAL (lhs)); } else { LONGEST low_bound; struct value *base; - struct type *type = check_typedef (value_type (lhs)); if (TYPE_CODE (type) == TYPE_CODE_ARRAY) { diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog index edc5079146..296878c33f 100644 --- a/gdb/testsuite/ChangeLog +++ b/gdb/testsuite/ChangeLog @@ -1,3 +1,7 @@ +2017-10-02 Tom Tromey + + * gdb.rust/simple.exp: Test ptype of a slice. + 2017-10-02 Tom Tromey * gdb.rust/simple.exp: Test index of slice. diff --git a/gdb/testsuite/gdb.rust/simple.exp b/gdb/testsuite/gdb.rust/simple.exp index 1a46317780..b01841f1e0 100644 --- a/gdb/testsuite/gdb.rust/simple.exp +++ b/gdb/testsuite/gdb.rust/simple.exp @@ -85,6 +85,25 @@ gdb_test "print fromslice" " = 3" gdb_test "print slice\[0\]" " = 3" gdb_test "print slice as &\[i32\]\[0\]" " = 3" +gdb_test_sequence "ptype slice" "" { + " = struct &\\\[i32\\\] \\{" + " data_ptr: i32 \\*," + " length: usize," + "\\}" +} +gdb_test_sequence "ptype &slice\[..\]" "" { + " = struct &\\\[i32\\\] \\{" + " data_ptr: i32 \\*," + " length: usize," + "\\}" +} +gdb_test_sequence "ptype &b\[..\]" "" { + " = struct &\\\[\\*gdb\\*\\\] \\{" + " data_ptr: i32 \\*," + " length: usize," + "\\}" +} + gdb_test "print x" " = \\(23, 25\\.5\\)" gdb_test "ptype x" " = \\(i32, f64\\)" gdb_test "print x as (i32,f64)" " = \\(23, 25\\.5\\)" -- 2.34.1