[llvm] [XCOFF] make related SD symbols as isFunction (PR #69553)

[via llvm-commits]

================
@@ -1242,10 +1242,8 @@ bool XCOFFSymbolRef::isFunction() const {
 
   const XCOFFCsectAuxRef CsectAuxRef = ExpCsectAuxEnt.get();
 
-  // A function definition should be a label definition.
-  // FIXME: This is not necessarily the case when -ffunction-sections is
-  // enabled.
-  if (!CsectAuxRef.isLabel())
+  // A function definition should not be a common type symbol.
----------------
diggerlin wrote:

add one more check symbol type=SD and symbol size is zero, return false. 

https://github.com/llvm/llvm-project/pull/69553