diff -u -r webkitgtk-2.16.5/Source/WTF/wtf/text/StringImpl.h webkitgtk-2.16.5-gcc7/Source/WTF/wtf/text/StringImpl.h
--- webkitgtk-2.16.5/Source/WTF/wtf/text/StringImpl.h	2017-02-20 17:20:15.000000000 +0100
+++ webkitgtk-2.16.5-gcc7/Source/WTF/wtf/text/StringImpl.h	2017-06-27 13:13:57.801527350 +0200
@@ -581,29 +581,7 @@
     // FIXME: Does this really belong in StringImpl?
     template <typename T> static void copyChars(T* destination, const T* source, unsigned numCharacters)
     {
-        if (numCharacters == 1) {
-            *destination = *source;
-            return;
-        }
-
-        if (numCharacters <= s_copyCharsInlineCutOff) {
-            unsigned i = 0;
-#if (CPU(X86) || CPU(X86_64))
-            const unsigned charsPerInt = sizeof(uint32_t) / sizeof(T);
-
-            if (numCharacters > charsPerInt) {
-                unsigned stopCount = numCharacters & ~(charsPerInt - 1);
-
-                const uint32_t* srcCharacters = reinterpret_cast<const uint32_t*>(source);
-                uint32_t* destCharacters = reinterpret_cast<uint32_t*>(destination);
-                for (unsigned j = 0; i < stopCount; i += charsPerInt, ++j)
-                    destCharacters[j] = srcCharacters[j];
-            }
-#endif
-            for (; i < numCharacters; ++i)
-                destination[i] = source[i];
-        } else
-            memcpy(destination, source, numCharacters * sizeof(T));
+        memcpy(destination, source, numCharacters * sizeof(T));
     }
 
     ALWAYS_INLINE static void copyChars(UChar* destination, const LChar* source, unsigned numCharacters)