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Auto merge of #63875 - philipc:issue-57822, r=michaelwoerister
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debuginfo: give unique names to closure and generator types

Closure types have been moved to the namespace where they
are defined, and both closure and generator type names now
include the disambiguator.

This fixes an exception when lldb prints nested closures.

Fixes #57822

I haven't included the `DW_AT_artificial` changes discussed in #57822 because they make the output worse IMO, but I can easily add these if still required. For example, for the new test case the output is now:
```
(lldb) p g
(issue_57822::main::closure-1) $1 = closure-1(closure(1))
```
but adding `DW_AT_artificial` changes this to:
```
(lldb) p g
(issue_57822::main::closure-1) $0 = closure-1 {

}
```

Note that nested generators didn't cause the exception. I haven't determined why, but I think it makes sense to add the disambiguator for them too. It feels like we still don't really understand why closures were causing an error though.

r? @michaelwoerister
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bors committed Aug 28, 2019
2 parents c422372 + 61ff27a commit 17e73e8
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Showing 4 changed files with 80 additions and 15 deletions.
10 changes: 7 additions & 3 deletions src/librustc_codegen_llvm/debuginfo/metadata.rs
Original file line number Diff line number Diff line change
Expand Up @@ -683,11 +683,13 @@ pub fn type_metadata(
}
ty::Closure(def_id, substs) => {
let upvar_tys : Vec<_> = substs.upvar_tys(def_id, cx.tcx).collect();
let containing_scope = get_namespace_for_item(cx, def_id);
prepare_tuple_metadata(cx,
t,
&upvar_tys,
unique_type_id,
usage_site_span).finalize(cx)
usage_site_span,
Some(containing_scope)).finalize(cx)
}
ty::Generator(def_id, substs, _) => {
let upvar_tys : Vec<_> = substs.prefix_tys(def_id, cx.tcx).map(|t| {
Expand Down Expand Up @@ -728,7 +730,8 @@ pub fn type_metadata(
t,
&tys,
unique_type_id,
usage_site_span).finalize(cx)
usage_site_span,
NO_SCOPE_METADATA).finalize(cx)
}
_ => {
bug!("debuginfo: unexpected type in type_metadata: {:?}", t)
Expand Down Expand Up @@ -1205,14 +1208,15 @@ fn prepare_tuple_metadata(
component_types: &[Ty<'tcx>],
unique_type_id: UniqueTypeId,
span: Span,
containing_scope: Option<&'ll DIScope>,
) -> RecursiveTypeDescription<'ll, 'tcx> {
let tuple_name = compute_debuginfo_type_name(cx.tcx, tuple_type, false);

let struct_stub = create_struct_stub(cx,
tuple_type,
&tuple_name[..],
unique_type_id,
NO_SCOPE_METADATA);
containing_scope);

create_and_register_recursive_type_forward_declaration(
cx,
Expand Down
14 changes: 10 additions & 4 deletions src/librustc_codegen_ssa/debuginfo/type_names.rs
Original file line number Diff line number Diff line change
Expand Up @@ -190,11 +190,17 @@ pub fn push_debuginfo_type_name<'tcx>(
// processing
visited.remove(t);
},
ty::Closure(..) => {
output.push_str("closure");
ty::Closure(def_id, ..) => {
output.push_str(&format!(
"closure-{}",
tcx.def_key(def_id).disambiguated_data.disambiguator
));
}
ty::Generator(..) => {
output.push_str("generator");
ty::Generator(def_id, ..) => {
output.push_str(&format!(
"generator-{}",
tcx.def_key(def_id).disambiguated_data.disambiguator
));
}
ty::Error |
ty::Infer(_) |
Expand Down
16 changes: 8 additions & 8 deletions src/test/debuginfo/generator-objects.rs
Original file line number Diff line number Diff line change
Expand Up @@ -10,31 +10,31 @@

// gdb-command:run
// gdb-command:print b
// gdb-check:$1 = generator_objects::main::generator {__0: 0x[...], <<variant>>: {__state: 0, 0: generator_objects::main::generator::Unresumed, 1: generator_objects::main::generator::Returned, 2: generator_objects::main::generator::Panicked, 3: generator_objects::main::generator::Suspend0 {[...]}, 4: generator_objects::main::generator::Suspend1 {[...]}}}
// gdb-check:$1 = generator_objects::main::generator-0 {__0: 0x[...], <<variant>>: {__state: 0, 0: generator_objects::main::generator-0::Unresumed, 1: generator_objects::main::generator-0::Returned, 2: generator_objects::main::generator-0::Panicked, 3: generator_objects::main::generator-0::Suspend0 {[...]}, 4: generator_objects::main::generator-0::Suspend1 {[...]}}}
// gdb-command:continue
// gdb-command:print b
// gdb-check:$2 = generator_objects::main::generator {__0: 0x[...], <<variant>>: {__state: 3, 0: generator_objects::main::generator::Unresumed, 1: generator_objects::main::generator::Returned, 2: generator_objects::main::generator::Panicked, 3: generator_objects::main::generator::Suspend0 {c: 6, d: 7}, 4: generator_objects::main::generator::Suspend1 {[...]}}}
// gdb-check:$2 = generator_objects::main::generator-0 {__0: 0x[...], <<variant>>: {__state: 3, 0: generator_objects::main::generator-0::Unresumed, 1: generator_objects::main::generator-0::Returned, 2: generator_objects::main::generator-0::Panicked, 3: generator_objects::main::generator-0::Suspend0 {c: 6, d: 7}, 4: generator_objects::main::generator-0::Suspend1 {[...]}}}
// gdb-command:continue
// gdb-command:print b
// gdb-check:$3 = generator_objects::main::generator {__0: 0x[...], <<variant>>: {__state: 4, 0: generator_objects::main::generator::Unresumed, 1: generator_objects::main::generator::Returned, 2: generator_objects::main::generator::Panicked, 3: generator_objects::main::generator::Suspend0 {[...]}, 4: generator_objects::main::generator::Suspend1 {c: 7, d: 8}}}
// gdb-check:$3 = generator_objects::main::generator-0 {__0: 0x[...], <<variant>>: {__state: 4, 0: generator_objects::main::generator-0::Unresumed, 1: generator_objects::main::generator-0::Returned, 2: generator_objects::main::generator-0::Panicked, 3: generator_objects::main::generator-0::Suspend0 {[...]}, 4: generator_objects::main::generator-0::Suspend1 {c: 7, d: 8}}}
// gdb-command:continue
// gdb-command:print b
// gdb-check:$4 = generator_objects::main::generator {__0: 0x[...], <<variant>>: {__state: 1, 0: generator_objects::main::generator::Unresumed, 1: generator_objects::main::generator::Returned, 2: generator_objects::main::generator::Panicked, 3: generator_objects::main::generator::Suspend0 {[...]}, 4: generator_objects::main::generator::Suspend1 {[...]}}}
// gdb-check:$4 = generator_objects::main::generator-0 {__0: 0x[...], <<variant>>: {__state: 1, 0: generator_objects::main::generator-0::Unresumed, 1: generator_objects::main::generator-0::Returned, 2: generator_objects::main::generator-0::Panicked, 3: generator_objects::main::generator-0::Suspend0 {[...]}, 4: generator_objects::main::generator-0::Suspend1 {[...]}}}

// === LLDB TESTS ==================================================================================

// lldb-command:run
// lldb-command:print b
// lldbg-check:(generator_objects::main::generator) $0 = generator(&0x[...])
// lldbg-check:(generator_objects::main::generator-0) $0 = generator-0(&0x[...])
// lldb-command:continue
// lldb-command:print b
// lldbg-check:(generator_objects::main::generator) $1 = generator(&0x[...])
// lldbg-check:(generator_objects::main::generator-0) $1 = generator-0(&0x[...])
// lldb-command:continue
// lldb-command:print b
// lldbg-check:(generator_objects::main::generator) $2 = generator(&0x[...])
// lldbg-check:(generator_objects::main::generator-0) $2 = generator-0(&0x[...])
// lldb-command:continue
// lldb-command:print b
// lldbg-check:(generator_objects::main::generator) $3 = generator(&0x[...])
// lldbg-check:(generator_objects::main::generator-0) $3 = generator-0(&0x[...])

#![feature(omit_gdb_pretty_printer_section, generators, generator_trait)]
#![omit_gdb_pretty_printer_section]
Expand Down
55 changes: 55 additions & 0 deletions src/test/debuginfo/issue-57822.rs
Original file line number Diff line number Diff line change
@@ -0,0 +1,55 @@
// This test makes sure that the LLDB pretty printer does not throw an exception
// for nested closures and generators.

// Require LLVM with DW_TAG_variant_part and a gdb that can read it.
// min-system-llvm-version: 8.0
// min-gdb-version: 8.2
// ignore-tidy-linelength

// compile-flags:-g

// === GDB TESTS ===================================================================================

// gdb-command:run

// gdb-command:print g
// gdb-check:$1 = issue_57822::main::closure-1 (issue_57822::main::closure-0 (1))

// gdb-command:print b
// gdb-check:$2 = issue_57822::main::generator-3 {__0: issue_57822::main::generator-2 {__0: 2, <<variant>>: {[...]}}, <<variant>>: {[...]}}

// === LLDB TESTS ==================================================================================

// lldb-command:run

// lldb-command:print g
// lldbg-check:(issue_57822::main::closure-1) $0 = closure-1(closure-0(1))

// lldb-command:print b
// lldbg-check:(issue_57822::main::generator-3) $1 = generator-3(generator-2(2))

#![feature(omit_gdb_pretty_printer_section, generators, generator_trait)]
#![omit_gdb_pretty_printer_section]

use std::ops::Generator;
use std::pin::Pin;

fn main() {
let mut x = 1;
let f = move || x;
let g = move || f();

let mut y = 2;
let mut a = move || {
y += 1;
yield;
};
let mut b = move || {
Pin::new(&mut a).resume();
yield;
};

zzz(); // #break
}

fn zzz() { () }

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