Merge pull request #11264 from BorisCarvajal/fix20923

Fix Issue 20923 - Redefinition of 'size_t' is affecting TypeStruct fu…
merged-on-behalf-of: Nicholas Wilson <thewilsonator@users.noreply.github.com>

Author: dlang-bot

src/dmd/clone.d

@@ -809,7 +809,7 @@ FuncDeclaration buildXtoHash(StructDeclaration sd, Scope* sc)
      * hash value will also contain the result of parent class's toHash().
      */
     const(char)[] code =
-        "size_t h = 0;" ~
+        ".object.size_t h = 0;" ~
         "foreach (i, T; typeof(p.tupleof))" ~
         // workaround https://issues.dlang.org/show_bug.cgi?id=17968
         "    static if(is(T* : const(.object.Object)*)) " ~

test/compilable/test20923.d

@@ -0,0 +1,13 @@
+version (D_LP64)
+{
+    alias size_t = uint;
+}
+else
+{
+    alias size_t = ulong;
+}
+
+struct S
+{
+    real not_reproduceable_without_this_variable;
+}