Remove a wrong multiplier on relocation offset computation

src/librustc_mir/interpret/memory.rs

@@ -707,10 +707,10 @@ impl<'a, 'mir, 'tcx, M: Machine<'a, 'mir, 'tcx>> Memory<'a, 'mir, 'tcx, M> {
                 new_relocations.extend(
                     relocations
                     .iter()
-                    .map(|&(offset, reloc)| {
-                    (offset + dest.offset - src.offset + (i * size * relocations.len() as u64),
-                     reloc)
-                    })
+                    .map(|&(offset, reloc)| (
+                        offset + dest.offset - src.offset + (i * size),
+                        reloc,
+                    ))
                 );
             }
 

src/test/ui/consts/promoted_regression.rs

@@ -0,0 +1,9 @@
+// compile-pass
+
+fn main() {
+    let _ = &[("", ""); 3];
+}
+
+const FOO: &[(&str, &str)] = &[("", ""); 3];
+const BAR: &[(&str, &str); 5] = &[("", ""); 5];
+const BAA: &[[&str; 12]; 11] = &[[""; 12]; 11];