[PATCH] D29609: [dsymutil] Follow dependencies during ODR uniquing

[Alexander Shaposhnikov via Phabricator via llvm-commits]

alexshap added a comment.

example without functions is a bit simpler:

preprocessed Source1.cpp:

  \# 1 "Header.h" 1
   typedef struct S *Sptr;
  \# 3 "Source1.cpp" 2
  Sptr ptr1;

preprocessed Source2.cpp:

  \# 1 "Header.h" 1
   typedef struct S *Sptr;
  \# 3 "Source1.cpp" 2
   struct S { int field; };
   Sptr ptr2;

A. "broken" order of the walked DIEs (while marking them as "kept"):

Source1.o: DW_TAG_variable -> /* parent walk */ -> DW_TAG_typedef -> DW_TAG_pointer_type -> DW_TAG_structure_type (forward declaration, can be ignored, that's ok)
Source2.o  DW_TAG_variable -> /* parent walk */ ->  looking at DW_TAG_typedef  (already seen, exactly at the same location (1 "Header.h" 1) , "continue" is executed and we don't "follow"
the attributes.

B. "fixed "order of the walked DIEs (while marking them as "kept"):
Source1.o: DW_TAG_variable -> /* parent walk */ -> DW_TAG_typedef -> DW_TAG_pointer_type -> DW_TAG_structure_type (forward declaration, can be ignored, that's ok)
Source2.o  DW_TAG_variable -> /* parent wak */ ->  looking at DW_TAG_typedef  (already seen, exactly at the same location (1 "Header.h" 1), marking it as ODRSeen) -> DW_TAG_pointer_type -> DW_TAG_structure_type -> DW_TAG_member -> DW_TAG_base_type


Repository:
  rL LLVM

https://reviews.llvm.org/D29609