[PATCH] D109703: [DebugInfo] Fix scope for local static variables

[Kristina Bessonova via Phabricator via cfe-commits]

krisb added a comment.

In D109703#2998155 <https://reviews.llvm.org/D109703#2998155>, @ellis wrote:

> I've added this to the added test case.
>
>   !18 = !DIImportedEntity(tag: DW_TAG_imported_declaration, scope: !4, entity: !19, line: 122)
>   !19 = !DIGlobalVariable(name: "imported_static_var", scope: !6, file: !5, line: 3, type: !10, isLocal: false, isDefinition: true)

Thank you for pointing to this! Just in case, do you have a C++ example, that reproduces the issue with imported static local declaration? I'm asking, cause in your example `DW_TAG_imported_declaration` has CU as a scope, while `DIGlobalVariable` is function-scoped. This looks a bit strange. I mean, `constructImportedEntityDIE()` called from `DwarfDebug::beginModule()` skips all local-scoped entities, and unless I'm missing something static locals shouldn't go here. Another call for  `constructImportedEntityDIE()` is from `DwarfCompileUnit::createScopeChildrenDIE` where I'd not expect any issue with parents.

But it seems imported declarations are broken not just for static locals, but for all inlined entities, for example

  namespace ns {
  inline __attribute__((always_inline))
  int foo() {
    int a = 42; 
    return a;
  }
  }
  
  int main() {
    using ns::foo;
    return foo();
  }

produces (with or w/o this patch) imported declaration for `foo()` that refers to an empty subprogram:

  x0000002a:   DW_TAG_namespace
                  DW_AT_name  ("ns")
  
  0x0000002f:     DW_TAG_subprogram
                    DW_AT_name  ("foo")
                    DW_AT_inline  (DW_INL_inlined)
  
  0x0000003f:       DW_TAG_variable
                      DW_AT_name  ("a")
  
  0x0000004a:       NULL
  
  0x0000004b:     DW_TAG_subprogram
  
  0x0000004c:     NULL
  
  0x00000054:   DW_TAG_subprogram
                  DW_AT_name  ("main")
  
  0x0000006d:     DW_TAG_imported_declaration
                    DW_AT_import  (0x0000004b)

while it should point to `0x0000002f`.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D109703/new/

https://reviews.llvm.org/D109703