fixup! add DocBrief

Author: Michael137

clang/include/clang/Driver/Options.td

@@ -4775,7 +4775,10 @@ defm structor_decl_linkage_names
                           "Attach linkage names to C++ constructor/destructor "
                           "declarations in DWARF."
                           "Implies -g.">,
-                  BothFlags<[], [ClangOption, CLOption, CC1Option]>>;
+                  BothFlags<[], [ClangOption, CLOption, CC1Option]>>,
+                  DocBrief<[{On some ABIs (e.g., Itanium), constructors and destructors may have multiple variants. Historically, when generating DWARF, Clang did not attach ``DW_AT_linkage_name``s to structor DIEs because there were multiple possible manglings (depending on the structor variant) that could be used. With ``-gstructor-decl-linkage-names``, for ABIs with structor variants, we attach a "unified" mangled name to structor declarations DIEs which debuggers can use to look up all the definitions for a structor declaration. E.g., a "unified" mangled name ``_ZN3FooC4Ev`` may have multiple definitions associated with it such as ``_ZN3FooC1Ev`` and ``_ZN3FooC2Ev``.
+
+Enabling this flag results in a better interactive debugging experience (both GDB and LLDB have support for understanding these "unified" linkage names). However, it comes with a significant increase in debug-info size (particularly the `.debug_str` section). As an escape hatch, users can disable this feature using ``-gno-structor-decl-linkage-names``.}]>;
 defm key_instructions : BoolGOption<"key-instructions",
     CodeGenOpts<"DebugKeyInstructions">, DefaultFalse,
     NegFlag<SetFalse>, PosFlag<SetTrue, [], [],