[llvm] Fix DW_TAG_template_alias refs in llvm-dwarfdump --verify (PR #89589)

[via llvm-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-llvm-binary-utilities

Author: Orlando Cazalet-Hyams (OCHyams)

<details>
<summary>Changes</summary>

A DW_TAG_template_alias referenced by a DW_AT_type incorrectly produces the error:

    error: DIE has DW_AT_type with incompatible tag DW_TAG_template_alias

Fix and add test.

---
Full diff: https://github.com/llvm/llvm-project/pull/89589.diff


2 Files Affected:

- (modified) llvm/include/llvm/BinaryFormat/Dwarf.def (+1-1) 
- (added) llvm/test/tools/llvm-dwarfdump/X86/verify_template_alias.yaml (+95) 


``````````diff
diff --git a/llvm/include/llvm/BinaryFormat/Dwarf.def b/llvm/include/llvm/BinaryFormat/Dwarf.def
index 8cf90de637a3d5..460a9264536bc0 100644
--- a/llvm/include/llvm/BinaryFormat/Dwarf.def
+++ b/llvm/include/llvm/BinaryFormat/Dwarf.def
@@ -203,7 +203,7 @@ HANDLE_DW_TAG(0x0040, shared_type, 3, DWARF, DW_KIND_TYPE)
 // New in DWARF v4:
 HANDLE_DW_TAG(0x0041, type_unit, 4, DWARF, DW_KIND_NONE)
 HANDLE_DW_TAG(0x0042, rvalue_reference_type, 4, DWARF, DW_KIND_TYPE)
-HANDLE_DW_TAG(0x0043, template_alias, 4, DWARF, DW_KIND_NONE)
+HANDLE_DW_TAG(0x0043, template_alias, 4, DWARF, DW_KIND_TYPE)
 // New in DWARF v5:
 HANDLE_DW_TAG(0x0044, coarray_type, 5, DWARF, DW_KIND_TYPE)
 HANDLE_DW_TAG(0x0045, generic_subrange, 5, DWARF, DW_KIND_NONE)
diff --git a/llvm/test/tools/llvm-dwarfdump/X86/verify_template_alias.yaml b/llvm/test/tools/llvm-dwarfdump/X86/verify_template_alias.yaml
new file mode 100644
index 00000000000000..2ccd2655e6a4cc
--- /dev/null
+++ b/llvm/test/tools/llvm-dwarfdump/X86/verify_template_alias.yaml
@@ -0,0 +1,95 @@
+# yaml2obj %s | llvm-dwarfdump --verify -
+
+## Check --verify doesn't fail when a DW_AT_type references a
+## DW_TAG_template_alias.
+##
+## $ cat test.cpp
+## template <typename T>
+## using A = T;
+## A<bool> a;
+##
+## $ clang++ test.cpp -g -gtemplate-alias -gsimple-template-names
+
+--- !ELF
+FileHeader:
+  Class:    ELFCLASS64
+  Data:     ELFDATA2LSB
+  Type:     ET_REL
+  Machine:  EM_X86_64
+DWARF:
+  debug_str:
+    - "clang version 19.0.0"
+    - "a"
+    - "A"
+    - "T"
+    - "bool"
+  debug_abbrev:
+    - Table:
+        - Code:            0x0000000000000001
+          Tag:             DW_TAG_compile_unit
+          Children:        DW_CHILDREN_yes
+          Attributes:
+            - Attribute:       DW_AT_name
+              Form:            DW_FORM_strp
+            - Attribute:       DW_AT_language
+              Form:            DW_FORM_data2
+        - Code:            0x0000000000000002
+          Tag:             DW_TAG_base_type
+          Children:        DW_CHILDREN_no
+          Attributes:
+            - Attribute:       DW_AT_name
+              Form:            DW_FORM_strp
+        - Code:            0x0000000000000003
+          Tag:             DW_TAG_template_alias
+          Children:        DW_CHILDREN_yes
+          Attributes:
+            - Attribute:       DW_AT_name
+              Form:            DW_FORM_strp
+            - Attribute:       DW_AT_type
+              Form:            DW_FORM_ref_addr
+        - Code:            0x0000000000000004
+          Tag:             DW_TAG_template_type_parameter
+          Children:        DW_CHILDREN_no
+          Attributes:
+            - Attribute:       DW_AT_name
+              Form:            DW_FORM_strp
+            - Attribute:       DW_AT_type
+              Form:            DW_FORM_ref_addr
+        - Code:            0x0000000000000005
+          Tag:             DW_TAG_variable
+          Children:        DW_CHILDREN_no
+          Attributes:
+            - Attribute:       DW_AT_name
+              Form:            DW_FORM_strp
+            - Attribute:       DW_AT_type
+              Form:            DW_FORM_ref_addr
+
+  debug_info:
+    - Version:         4
+      AbbrOffset:      0x0000000000000000
+      AddrSize:        8
+      Entries:
+        - AbbrCode:        0x00000001
+          Values:
+            - Value:           0x0000000000000000
+            - Value:           0x0000000000000021
+        - AbbrCode:        0x00000002
+          Values:
+            - Value:           0x000000000000001b
+        - AbbrCode:        0x00000003
+          Values:
+            - Value:           0x0000000000000017
+            - Value:           0x0000000000000012
+        - AbbrCode:        0x00000004
+          Values:
+            - Value:           0x0000000000000019
+            - Value:           0x0000000000000012
+        - AbbrCode:        0x00000000
+          Values:          []
+        - AbbrCode:        0x00000005
+          Values:
+            - Value:           0x0000000000000015
+            - Value:           0x0000000000000017
+        - AbbrCode:        0x00000000
+          Values:          []
+...

``````````

</details>


https://github.com/llvm/llvm-project/pull/89589