diff --git a/uppsrc/CodeEditor/CSyntax.cpp b/uppsrc/CodeEditor/CSyntax.cpp
index decca4948..12526f906 100644
--- a/uppsrc/CodeEditor/CSyntax.cpp
+++ b/uppsrc/CodeEditor/CSyntax.cpp
@@ -79,7 +79,7 @@ static WString sReadLn(const wchar *p)
 		else
 			wbuf.Cat(*p++);
 	}
-	return wbuf;
+	return WString(wbuf);
 }
 
 int LastC(const wchar *b, const wchar *e)
diff --git a/uppsrc/Core/CharSet.cpp b/uppsrc/Core/CharSet.cpp
index a52b2a206..a6839e385 100644
--- a/uppsrc/Core/CharSet.cpp
+++ b/uppsrc/Core/CharSet.cpp
@@ -2053,7 +2053,7 @@ WString ToUnicode(const char *src, int l, byte charset)
 		return FromUtf8(src, l);
 	WStringBuffer result(l);
 	ToUnicode(result, src, l, charset);
-	return result;
+	return WString(result);
 }
 
 WString ToUnicode(const String& src, byte charset)
@@ -2068,7 +2068,7 @@ String FromUnicodeBuffer(const wchar *src, int len, byte charset, int defchar)
 		return ToUtf8(src, len);
 	StringBuffer result(len);
 	FromUnicode(result, src, len, charset, defchar);
-	return result;
+	return String(result);
 }
 
 String FromUnicodeBuffer(const wchar *src)
@@ -2094,7 +2094,7 @@ String ToCharset(byte charset, const String& src, byte scharset, int def)
 		return ToUtf8(ToUnicode(src, scharset));
 	StringBuffer result(slen);
 	ConvertCharset(result, charset, src, scharset, slen);
-	return result;
+	return String(result);
 }
 
 WString InitCaps(const wchar *s)
@@ -2125,7 +2125,7 @@ WString InitCaps(const WString& s)
 			r[i] = ToLower(c);
 		spc = !IsLeNum(c);
 	}
-	return r;
+	return WString(r);
 }
 
 WString ToUpper(const WString& w)
@@ -2133,7 +2133,7 @@ WString ToUpper(const WString& w)
 	int l = w.GetLength();
 	WStringBuffer r(l);
 	ToUpper(r, w, l);
-	return r;
+	return WString(r);
 }
 
 WString ToLower(const WString& w)
@@ -2141,7 +2141,7 @@ WString ToLower(const WString& w)
 	int l = w.GetLength();
 	WStringBuffer r(l);
 	ToLower(r, w, l);
-	return r;
+	return WString(r);
 }
 
 WString ToAscii(const WString& w)
@@ -2149,7 +2149,7 @@ WString ToAscii(const WString& w)
 	int l = w.GetLength();
 	WStringBuffer r(l);
 	ToAscii(r, w, l);
-	return r;
+	return WString(r);
 }
 
 String InitCaps(const char *s, byte charset)
@@ -2165,7 +2165,7 @@ String ToUpper(const char *s, byte charset)
 	int l = (int)strlen(s);
 	StringBuffer r(l);
 	ToUpper(r, s, l, charset);
-	return r;
+	return String(r);
 }
 
 String ToLower(const char *s, byte charset)
@@ -2176,7 +2176,7 @@ String ToLower(const char *s, byte charset)
 	int l = (int)strlen(s);
 	StringBuffer r(l);
 	ToLower(r, s, l, charset);
-	return r;
+	return String(r);
 }
 
 String ToAscii(const char *s, byte charset)
@@ -2187,7 +2187,7 @@ String ToAscii(const char *s, byte charset)
 	int l = (int)strlen(s);
 	StringBuffer r(l);
 	ToAscii(r, s, l, charset);
-	return r;
+	return String(r);
 }
 
 String ToUpper(const String& s, byte charset)
@@ -2198,7 +2198,7 @@ String ToUpper(const String& s, byte charset)
 	int l = s.GetLength();
 	StringBuffer r(l);
 	ToUpper(r, s, l, charset);
-	return r;
+	return String(r);
 }
 
 String ToLower(const String& s, byte charset)
@@ -2209,7 +2209,7 @@ String ToLower(const String& s, byte charset)
 	int l = s.GetLength();
 	StringBuffer r(l);
 	ToLower(r, s, l, charset);
-	return r;
+	return String(r);
 }
 
 String ToAscii(const String& s, byte charset)
@@ -2220,7 +2220,7 @@ String ToAscii(const String& s, byte charset)
 	int l = s.GetLength();
 	StringBuffer r(l);
 	ToAscii(r, s, l, charset);
-	return r;
+	return String(r);
 }
 
 String ToUpperAscii(const String& s, byte charset)
@@ -2231,7 +2231,7 @@ String ToUpperAscii(const String& s, byte charset)
 	int l = s.GetLength();
 	StringBuffer r(l);
 	ToAscii(r, s, l, charset);
-	return r;
+	return String(r);
 }
 
 String ToLowerAscii(const String& s, byte charset)
@@ -2242,7 +2242,7 @@ String ToLowerAscii(const String& s, byte charset)
 	int l = s.GetLength();
 	StringBuffer r(l);
 	ToAscii(r, s, l, charset);
-	return r;
+	return String(r);
 }
 
 bool IsDoubleWidth(int c)
diff --git a/uppsrc/Core/Format.cpp b/uppsrc/Core/Format.cpp
index a3c05640d..6ab51bd1c 100644
--- a/uppsrc/Core/Format.cpp
+++ b/uppsrc/Core/Format.cpp
@@ -64,7 +64,7 @@ String FormatIntBase(int i, int base, int width, char lpad, int sign, bool upper
 	if(dwd < width)
 		memset(o, lpad, pad);
 	memcpy8(o + pad, p, dwd);
-	return out;
+	return String(out);
 }
 
 String FormatInt(int i)
@@ -382,7 +382,7 @@ String FormatDoubleExp(double d, int digits, int flags, int fill_exp)
 	}
 	out.Cat(flags & FD_CAP_E ? 'E' : 'e');
 	out.Cat(FormatIntDec(exp, fill_exp, '0', flags & FD_SIGN_EXP));
-	return out;
+	return String(out);
 }
 
 String FormatDate(Date date, const char *format, int language)
@@ -577,7 +577,7 @@ String IntFormatter(const Formatting& f)
 	StringBuffer q;
 	q.SetLength(1000);
 	q.SetLength(sprintf(q, '%' + f.format + f.id, (int)f.arg));
-	return q;
+	return String(q);
 }
 
 String Int64Formatter(const Formatting& f)
@@ -585,7 +585,7 @@ String Int64Formatter(const Formatting& f)
 	StringBuffer q;
 	q.SetLength(1000);
 	q.SetLength(sprintf(q, '%' + f.format + f.id, (int64)f.arg));
-	return q;
+	return String(q);
 }
 
 String IntLowerAlphaFormatter(const Formatting& f)
@@ -1148,7 +1148,7 @@ String DeFormat(const char *text)
 			x.Cat('%');
 		x.Cat(*text++);
 	}
-	return x;
+	return String(x);
 }
 
 }
diff --git a/uppsrc/Core/Huge.cpp b/uppsrc/Core/Huge.cpp
index f69f26a16..7805c6079 100644
--- a/uppsrc/Core/Huge.cpp
+++ b/uppsrc/Core/Huge.cpp
@@ -41,7 +41,7 @@ String Huge::Get() const
 		Panic("String is too big!");
 	StringBuffer sb((int)size);
 	Get(~sb, 0, size);
-	return sb;
+	return String(sb);
 }
 
 }
\ No newline at end of file
diff --git a/uppsrc/Core/InetUtil.cpp b/uppsrc/Core/InetUtil.cpp
index 326a684e3..a1553c010 100644
--- a/uppsrc/Core/InetUtil.cpp
+++ b/uppsrc/Core/InetUtil.cpp
@@ -124,7 +124,7 @@ String UrlEncode(const char *p, const char *e)
 		else
 			out << '%' << hex_digits[(*p >> 4) & 15] << hex_digits[*p & 15];
 	}
-	return out;
+	return String(out);
 }
 
 String UrlEncode(const char *s, int len)
@@ -156,7 +156,7 @@ String UrlDecode(const char *b, const char *e)
 		}
 		else
 			out.Cat(*p);
-	return out;
+	return String(out);
 }
 
 String UrlDecode(const char *s, int len)
@@ -179,7 +179,7 @@ String QPEncode(const char* s)
 			r.Cat(s[0]);
 			len++;
 		}
-		else 
+		else
 		if(s[0] == '\r')
 			;
 		else
@@ -209,7 +209,7 @@ String QPEncode(const char* s)
 		}
 		s++;
 	}
-	return r;
+	return String(r);
 }
     
 String QPDecode(const char *s, bool underscore_to_space)
@@ -232,7 +232,7 @@ String QPDecode(const char *s, bool underscore_to_space)
 		else
 			r.Cat(c);
 	}
-	return r;
+	return String(r);
 }
 
 String Base64Encode(const char *_b, const char *_e)
@@ -272,7 +272,7 @@ String Base64Encode(const char *_b, const char *_e)
 		p[2] = encoder[(b[1] << 2) & 0x3C];
 		p[3] = '=';
 	}
-	return s;
+	return String(s);
 }
 
 String Base64Encode(const char *b, int len)
@@ -330,7 +330,7 @@ String Base64Decode(const char *b, const char *e)
 				out.Cat((c[2] << 6) | (c[3] >> 0));
 		}
 	}
-	return out;
+	return String(out);
 }
 
 String Base64Decode(const char *s, int len)
diff --git a/uppsrc/Core/Socket.cpp b/uppsrc/Core/Socket.cpp
index c93b6d307..408b571d5 100644
--- a/uppsrc/Core/Socket.cpp
+++ b/uppsrc/Core/Socket.cpp
@@ -834,7 +834,7 @@ String TcpSocket::Get(int count)
 	if(!done && IsEof())
 		return String::GetVoid();
 	out.SetLength(done);
-	return out;
+	return String(out);
 }
 
 bool  TcpSocket::GetAll(void *buffer, int len)
diff --git a/uppsrc/Core/SplitMerge.cpp b/uppsrc/Core/SplitMerge.cpp
index 48618ca7d..7f201381f 100644
--- a/uppsrc/Core/SplitMerge.cpp
+++ b/uppsrc/Core/SplitMerge.cpp
@@ -173,7 +173,7 @@ T Join_(const Vector<T>& im, const T& delim, bool ignoreempty) {
 			r.Cat(im[i]);
 			next = true;
 		}
-	return r;
+	return T(r);
 }
 
 String Join(const Vector<String>& im, const String& delim, bool ignoreempty) {
diff --git a/uppsrc/Core/Stream.cpp b/uppsrc/Core/Stream.cpp
index e67a0316a..92e9df196 100644
--- a/uppsrc/Core/Stream.cpp
+++ b/uppsrc/Core/Stream.cpp
@@ -176,7 +176,7 @@ String Stream::Get(int size)
 	StringBuffer b(size);
 	int n = Get(~b, size);
 	b.SetCount(n);
-	return b;
+	return String(b);
 }
 
 String Stream::GetAll(int size)
@@ -1218,7 +1218,7 @@ String LoadStream(Stream& in) {
 			StringBuffer s((int)size);
 			in.Get(s, (int)size);
 			if(!in.IsError())
-				return s;
+				return String(s);
 		}
 	}
 	return String::GetVoid();
diff --git a/uppsrc/Core/Utf.cpp b/uppsrc/Core/Utf.cpp
index 47360b734..3acf1bd32 100644
--- a/uppsrc/Core/Utf.cpp
+++ b/uppsrc/Core/Utf.cpp
@@ -53,7 +53,7 @@ String ToUtf8(const wchar *s, int len)
 	StringBuffer r;
 	r.Reserve(len);
 	FromUtf16_([&](const wchar *, dword code) { ToUtf8_([&](char c) { r.Cat(c); }, code); }, s, len);
-	return r;
+	return String(r);
 }
 
 int Utf16Len(const dword *s, int len)
@@ -76,7 +76,7 @@ WString ToUtf16(const dword *s, int len)
 	r.Reserve(len);
 	for(const dword *lim = s + len; s < lim; s++)
 		ToUtf16_([&](wchar c) { r.Cat(c); }, *s);
-	return r;
+	return WString(r);
 }
 
 int Utf16Len(const char *s, int len)
@@ -95,7 +95,7 @@ WString ToUtf16(const char *s, int len)
 {
 	WStringBuffer r;
 	FromUtf8_([&](const byte *, dword code) { ToUtf16_([&](wchar c) { r.Cat(c); }, code); }, s, len);
-	return r;
+	return WString(r);
 }
 
 int Utf32Len(const char *s, int len)
@@ -146,7 +146,7 @@ String Utf8ToAscii(const String& src)
 	while(s < lim)
 		*t++ = (byte)*s < 128 ? *s++ : ToAscii(FetchUtf8(s, lim));
 	r.SetLength(int(t - ~r));
-	return r;
+	return String(r);
 }
 
 String Utf8ToUpperAscii(const String& src)
@@ -160,7 +160,7 @@ String Utf8ToUpperAscii(const String& src)
 		*t++ = (byte)*s <= 'Z' ? *s++ : ToUpperAscii(FetchUtf8(s, lim));
 	}
 	r.SetLength(int(t - ~r));
-	return r;
+	return String(r);
 }
 
 String Utf8ToLowerAscii(const String& src)
@@ -173,7 +173,7 @@ String Utf8ToLowerAscii(const String& src)
 	while(s < lim)
 		*t++ = ToLowerAscii(FetchUtf8(s, lim));
 	r.SetLength(int(t - ~r));
-	return r;
+	return String(r);
 }
 
 };
diff --git a/uppsrc/Core/Util.cpp b/uppsrc/Core/Util.cpp
index f912e622a..f311e3cae 100644
--- a/uppsrc/Core/Util.cpp
+++ b/uppsrc/Core/Util.cpp
@@ -392,13 +392,13 @@ String HexString(const byte *s, int count, int sep, int sepchr)
 	for(;;) {
 		for(int q = 0; q < sep; q++) {
 			if(i >= count)
-				return b;
+				return String(b);
 			*t++ = itoc[(s[i] & 0xf0) >> 4];
 			*t++ = itoc[s[i] & 0x0f];
 			i++;
 		}
 		if(i >= count)
-			return b;
+			return String(b);
 		*t++ = sepchr;
 	}
 }
@@ -467,7 +467,7 @@ String NormalizeSpaces(const char *s)
 		else
 			r.Cat(*s++);
 	}
-	return r;
+	return String(r);
 }
 
 String NormalizeSpaces(const char *s, const char *end)
@@ -485,7 +485,7 @@ String NormalizeSpaces(const char *s, const char *end)
 		else
 			r.Cat(*s++);
 	}
-	return r;
+	return String(r);
 }
 
 String CsvString(const String& text)
@@ -569,7 +569,7 @@ String CompressLog(const char *s)
 		else
 			result.Cat(b, s);
 	}
-	return result;
+	return String(result);
 }
 
 int ChNoInvalid(int c)
@@ -599,7 +599,7 @@ String ToSystemCharset(const String& src, int cp)
 	if(q <= 0)
 		return src;
 	b.SetCount(q);
-	return b;
+	return String(b);
 }
 
 String ToSystemCharset(const String& src)
diff --git a/uppsrc/Core/Vcont.cpp b/uppsrc/Core/Vcont.cpp
index 1b5070341..5385bd1e2 100644
--- a/uppsrc/Core/Vcont.cpp
+++ b/uppsrc/Core/Vcont.cpp
@@ -107,7 +107,7 @@ String Bits::ToString() const
 	StringBuffer ss;
 	for(int i = GetLast(); i >= 0; i--)
 		ss << FormatIntHex(bp[i]);
-	return ss;
+	return String(ss);
 }
 
 void Bits::Serialize(Stream& s)
diff --git a/uppsrc/Core/Win32Util.cpp b/uppsrc/Core/Win32Util.cpp
index 97663273b..b2aeebc62 100644
--- a/uppsrc/Core/Win32Util.cpp
+++ b/uppsrc/Core/Win32Util.cpp
@@ -61,7 +61,7 @@ String AsString(const wchar_t *buffer, int count) { // Convert with code page...
 	StringBuffer temp(count);
 	for(char *p = temp, *e = p + count; p < e;)
 		*p++ = (char)*buffer++;
-	return temp;
+	return String(temp);
 }
 
 String AsString(const wchar_t *buffer, const wchar_t *end) {
@@ -90,7 +90,7 @@ String GetWinRegString(const char *value, const char *path, HKEY base_key, dword
 		len--;
 	raw_len.SetLength(len);
 	RegCloseKey(key);
-	return raw_len;
+	return String(raw_len);
 }
 
 int GetWinRegInt(const char *value, const char *path, HKEY base_key, dword wow) {
diff --git a/uppsrc/Core/XML.cpp b/uppsrc/Core/XML.cpp
index ebec13fd4..f90bf8d73 100644
--- a/uppsrc/Core/XML.cpp
+++ b/uppsrc/Core/XML.cpp
@@ -24,7 +24,7 @@ String DeXml(const char *s, byte charset, bool escapelf)
 	StringBuffer result;
 	for(; *s; s++)
 		sDeXmlChar(result, *s, charset, escapelf);
-	return result;
+	return String(result);
 }
 
 String DeXml(const char *s, const char *end, byte charset, bool escapelf)
@@ -34,7 +34,7 @@ String DeXml(const char *s, const char *end, byte charset, bool escapelf)
 	StringBuffer result;
 	for(; s < end; s++)
 		sDeXmlChar(result, *s, charset, escapelf);
-	return result;
+	return String(result);
 }
 
 String DeXml(const String& s, byte charset, bool escapelf)
@@ -51,21 +51,21 @@ String XmlHeader(const char *encoding, const char *version, const char *standalo
 	if(standalone)
 		r << " standalone=\"" << standalone << "\"";
 	r << " ?>\r\n";
-	return r;
+	return String(r);
 }
 
 String XmlPI(const char *text)
 {
 	StringBuffer r;
 	r << "<?" << text << "?>\r\n";
-	return r;
+	return String(r);
 }
 
 String XmlDecl(const char *text)
 {
 	StringBuffer r;
 	r << "<!" << text << ">\r\n";
-	return r;
+	return String(r);
 }
 
 String XmlDocType(const char *text)
@@ -82,7 +82,7 @@ String XmlComment(const char *text)
 {
 	StringBuffer out;
 	out << "<!-- " << text << " -->\r\n";
-	return out;
+	return String(out);
 }
 
 String  XmlTag::operator()()
@@ -120,7 +120,7 @@ String  XmlTag::operator()(const char *text)
 		else
 		if(first) {
 			r << text << end;
-			return r;
+			return String(r);
 		}
 		first = false;
 		wasslash = false;
@@ -142,7 +142,7 @@ String  XmlTag::operator()(const char *text)
 	if(!first)
 		r << "\r\n";
 	r << end;
-	return r;
+	return String(r);
 }
 
 String  XmlTag::Text(const char *text, byte charset)
@@ -707,7 +707,7 @@ String XmlParser::ReadTextE()
 			out.Cat(t);
 		else if(IsEnd()) {
 			PassEnd();
-			return out;
+			return String(out);
 		}
 		else
 			Skip();
diff --git a/uppsrc/Core/parser.cpp b/uppsrc/Core/parser.cpp
index 3171aeb54..89fa1353d 100644
--- a/uppsrc/Core/parser.cpp
+++ b/uppsrc/Core/parser.cpp
@@ -196,7 +196,7 @@ String CParser::ReadIdt() {
 		result.Cat(*term++);
 	}
 	DoSpaces();
-	return result;
+	return String(result);
 }
 
 bool CParser::IsInt() const {
@@ -381,7 +381,7 @@ String CParser::ReadOneString(int delim, bool chkend) {
 		if(*term == delim) {
 			term++;
 			DoSpaces();
-			return result;
+			return String(result);
 		}
 		else
 		if(*term == '\\') {
@@ -452,16 +452,16 @@ String CParser::ReadOneString(int delim, bool chkend) {
 			if((byte)*term < ' ' && *term != '\t') {
 				if(chkend) {
 					ThrowError("Unterminated string");
-					return result;
+					return String(result);
 				}
 				if(*term == '\0')
-					return result;
+					return String(result);
 			}
 			result.Cat(*term++);
 		}
 	}
 	DoSpaces();
-	return result;
+	return String(result);
 }
 
 String CParser::ReadOneString(bool chkend)
@@ -700,7 +700,7 @@ String AsCString(const char *s, const char *lim, int linemax, const char *linepf
 		s++;
 	}
 	t.Cat('\"');
-	return t;
+	return String(t);
 }
 
 String AsCString(const char *s, int linemax, const char *linepfx, dword flags)
diff --git a/uppsrc/Core/z.cpp b/uppsrc/Core/z.cpp
index 73f058221..18cc13f98 100644
--- a/uppsrc/Core/z.cpp
+++ b/uppsrc/Core/z.cpp
@@ -490,7 +490,7 @@ String FastCompress(const void *s, int sz)
 	int clen = LZ4_compress_default((const char *)s, ~b + sizeof(int), sz, (int)maxsize);
 	b.SetCount(clen + sizeof(int));
 	b.Shrink();
-	return b;
+	return String(b);
 }
 
 String FastCompress(const String& s)
@@ -503,7 +503,7 @@ String FastDecompress(const String& data)
 	int sz = *(int *)~data;
 	StringBuffer b(sz);
 	LZ4_decompress_safe(~data + sizeof(int), b, data.GetCount() - sizeof(int), sz);
-	return b;
+	return String(b);
 }
 
 // following function is used in both plugin/lz4 and plugin/zstd
diff --git a/uppsrc/CppBase/Parser.cpp b/uppsrc/CppBase/Parser.cpp
index 86f43b9b0..857eb11e7 100644
--- a/uppsrc/CppBase/Parser.cpp
+++ b/uppsrc/CppBase/Parser.cpp
@@ -483,7 +483,7 @@ String Parser::ReadOper(bool& castoper) {
 			spc = true;
 		p++;
 	}
-	return r;
+	return String(r);
 }
 
 String Parser::Name(String& name, bool& castoper, bool& oper)
diff --git a/uppsrc/CppBase/cpp.cpp b/uppsrc/CppBase/cpp.cpp
index 32c95572e..3de54a7b9 100644
--- a/uppsrc/CppBase/cpp.cpp
+++ b/uppsrc/CppBase/cpp.cpp
@@ -100,7 +100,7 @@ String Cpp::Expand(const char *s)
 										prefix_macro = bid;
 									else
 										prefix_macro = String(' ', 1) + bid; // do not want to emit grounding in body
-									return r;
+									return String(r);
 								}
 								else
 								if(*s == '\"' || *s == '\'')
@@ -147,7 +147,7 @@ String Cpp::Expand(const char *s)
 		else
 			r.Cat(*s++);
 	}
-	return r;
+	return String(r);
 }
 
 void Cpp::DoFlatInclude(const String& header_path)
diff --git a/uppsrc/CtrlCore/MetaFile.cpp b/uppsrc/CtrlCore/MetaFile.cpp
index 4557574c6..066ef2df4 100644
--- a/uppsrc/CtrlCore/MetaFile.cpp
+++ b/uppsrc/CtrlCore/MetaFile.cpp
@@ -130,7 +130,7 @@ String WinMetaFile::Get() const
 	int size = ::GetEnhMetaFileBits(hemf, 0, 0);
 	StringBuffer b(size);
 	::GetEnhMetaFileBits(hemf, size, (BYTE *)~b);
-	return b;
+	return String(b);
 }
 
 void WinMetaFile::Serialize(Stream& s) {
diff --git a/uppsrc/CtrlCore/Win32Clip.cpp b/uppsrc/CtrlCore/Win32Clip.cpp
index b31c9a7f7..eeadd947a 100644
--- a/uppsrc/CtrlCore/Win32Clip.cpp
+++ b/uppsrc/CtrlCore/Win32Clip.cpp
@@ -408,7 +408,7 @@ String sDib(const Value& image)
 	byte *p = (byte *)~b;
 	memcpy(p, &header, sizeof(header));
 	memcpy(p + sizeof(header), ~img, 4 * img.GetLength());
-	return b;
+	return String(b);
 }
 
 String sImage(const Value& image)
diff --git a/uppsrc/CtrlLib/ChWin32.cpp b/uppsrc/CtrlLib/ChWin32.cpp
index b90ba028a..88e938a67 100644
--- a/uppsrc/CtrlLib/ChWin32.cpp
+++ b/uppsrc/CtrlLib/ChWin32.cpp
@@ -194,7 +194,7 @@ struct Win32ImageMaker : ImageMaker {
 		RawCat(key, part);
 		RawCat(key, state);
 		RawCat(key, sz);
-		return key;
+		return String(key);
 	}
 	virtual Image Make() const {
 		Rect rr(sz);
diff --git a/uppsrc/CtrlLib/Text.cpp b/uppsrc/CtrlLib/Text.cpp
index 082dfcf1b..f65905011 100644
--- a/uppsrc/CtrlLib/Text.cpp
+++ b/uppsrc/CtrlLib/Text.cpp
@@ -678,7 +678,7 @@ WString TextCtrl::GetW(int64 pos, int size) const
 		if(size == 0) break;
 		pos = 0;
 	}
-	return r;
+	return WString(r);
 }
 
 String TextCtrl::Get(int64 pos, int size, byte charset) const
@@ -707,7 +707,7 @@ String TextCtrl::Get(int64 pos, int size, byte charset) const
 			if(size == 0) break;
 			pos = 0;
 		}
-		return r;
+		return String(r);
 	}
 	return FromUnicode(GetW(pos, size), charset);
 }
diff --git a/uppsrc/Draw/DrawText.cpp b/uppsrc/Draw/DrawText.cpp
index 30ea03b13..9c98a5382 100644
--- a/uppsrc/Draw/DrawText.cpp
+++ b/uppsrc/Draw/DrawText.cpp
@@ -17,7 +17,7 @@ WString TextUnicode(const char *s, int n, byte cs, Font font)
 			*t++ = *s++;
 			n--;
 		}
-		return b;
+		return WString(b);
 	}
 #endif
 	return ToUnicode(s, n, cs);
diff --git a/uppsrc/Draw/ImageBlit.cpp b/uppsrc/Draw/ImageBlit.cpp
index e39191220..aa03efbed 100644
--- a/uppsrc/Draw/ImageBlit.cpp
+++ b/uppsrc/Draw/ImageBlit.cpp
@@ -79,7 +79,7 @@ String PackRLE(const RGBA *s, int len)
 			}
 		}
 	}
-	return r;
+	return String(r);
 }
 
 int Premultiply(RGBA *t, const RGBA *s, int len)
diff --git a/uppsrc/Draw/MakeCache.cpp b/uppsrc/Draw/MakeCache.cpp
index 9d962a382..0d4f437f9 100644
--- a/uppsrc/Draw/MakeCache.cpp
+++ b/uppsrc/Draw/MakeCache.cpp
@@ -13,7 +13,7 @@ struct scImageMaker : ValueMaker {
 		s.Cat(typeid(*m).name());
 		RawCat(s, paintonly);
 		s.Cat(m->Key());
-		return s;
+		return String(s);
 	}
 	virtual int    Make(Value& object) const {
 		Image img = m->Make();
@@ -140,7 +140,7 @@ struct sCachedRescale : public ImageMaker
 		RawCat(h, sz.cy);
 		RawCat(h, img.GetSerialId());
 		RawCat(h, filter);
-		return h;
+		return String(h);
 	}
 
 	virtual Image Make() const {
@@ -195,7 +195,7 @@ struct sColorize : public ImageMaker
 		StringBuffer h;
 		RawCat(h, color);
 		RawCat(h, img.GetSerialId());
-		return h;
+		return String(h);
 	}
 
 	virtual Image Make() const {
diff --git a/uppsrc/Draw/SDrawText.cpp b/uppsrc/Draw/SDrawText.cpp
index b99c32cb1..2f34f6277 100644
--- a/uppsrc/Draw/SDrawText.cpp
+++ b/uppsrc/Draw/SDrawText.cpp
@@ -28,7 +28,7 @@ struct sMakeTextGlyph : public ImageMaker
 		RawCat(h, angle);
 		RawCat(h, color);
 		RawCat(h, yy);
-		return h;
+		return String(h);
 	}
 
 	virtual Image Make() const {
diff --git a/uppsrc/Esc/EscArray.cpp b/uppsrc/Esc/EscArray.cpp
index 447fe402c..6b2675745 100644
--- a/uppsrc/Esc/EscArray.cpp
+++ b/uppsrc/Esc/EscArray.cpp
@@ -106,7 +106,7 @@ EscValue::operator WString() const
 					s.Cat(c);
 			}
 	}
-	return s;
+	return WString(s);
 }
 
 void EscValue::InitString(const WString& s)
diff --git a/uppsrc/Esc/EscValue.cpp b/uppsrc/Esc/EscValue.cpp
index a1c6f8dc8..6b8247207 100644
--- a/uppsrc/Esc/EscValue.cpp
+++ b/uppsrc/Esc/EscValue.cpp
@@ -280,7 +280,7 @@ String EscValue::ToString(int maxlen, int indent_step, bool hex, int indent) con
 			r << lambda->arg[i];
 		}
 		r << ")\n" << lambda->code;
-		return r;
+		return String(r);
 	case ESC_MAP:
 		r << ind << "{ ";
 		int c = min(map->map.GetCount(), 100);
diff --git a/uppsrc/Oracle/Oci8.cpp b/uppsrc/Oracle/Oci8.cpp
index d19f310d3..d6bd3eaa8 100644
--- a/uppsrc/Oracle/Oci8.cpp
+++ b/uppsrc/Oracle/Oci8.cpp
@@ -1707,7 +1707,7 @@ WString OracleClob::Read()
 	out.SetCount(nchars);
 	Seek(0);
 	Stream::Get(out, 2 * nchars);
-	return out;
+	return WString(out);
 }
 
 void OracleClob::Write(const WString& w)
diff --git a/uppsrc/PdfDraw/PdfDraw.cpp b/uppsrc/PdfDraw/PdfDraw.cpp
index ac9af2da6..4ccb066fe 100644
--- a/uppsrc/PdfDraw/PdfDraw.cpp
+++ b/uppsrc/PdfDraw/PdfDraw.cpp
@@ -277,7 +277,7 @@ String PdfDraw::PdfString(const char *s)
 		b.Cat(*s++);
 	}
 	b.Cat(')');
-	return b;
+	return String(b);
 }
 
 void PdfDraw::PutFontHeight(int fi, double ht)
diff --git a/uppsrc/RichText/EncodeHTML.cpp b/uppsrc/RichText/EncodeHTML.cpp
index a3de81129..9a86aff25 100644
--- a/uppsrc/RichText/EncodeHTML.cpp
+++ b/uppsrc/RichText/EncodeHTML.cpp
@@ -363,7 +363,7 @@ String DefaultHtmlObjectSaver::GetHtml(const RichObject& object, const String& l
 		PNGEncoder png;
 		png.SaveFile(AppendFileName(outdir, lname), object.ToImage(psz));
 	}
-	return html;
+	return String(html);
 }
 
 String EncodeHtml(const RichText& text, Index<String>& css,
diff --git a/uppsrc/RichText/EncodeQtf.cpp b/uppsrc/RichText/EncodeQtf.cpp
index dac483079..43848961b 100644
--- a/uppsrc/RichText/EncodeQtf.cpp
+++ b/uppsrc/RichText/EncodeQtf.cpp
@@ -562,7 +562,7 @@ String DeQtf(const char *s) {
 			r.Cat(*s);
 		}
 	}
-	return r;
+	return String(r);
 }
 
 String DeQtfLf(const char *s) {
@@ -580,7 +580,7 @@ String DeQtfLf(const char *s) {
 			r.Cat("-|");
 		s++;
 	}
-	return r;
+	return String(r);
 }
 
 RichText AsRichText(const RichObject& obj)
diff --git a/uppsrc/RichText/ParaPaint.cpp b/uppsrc/RichText/ParaPaint.cpp
index f75fcdc50..7357ce991 100644
--- a/uppsrc/RichText/ParaPaint.cpp
+++ b/uppsrc/RichText/ParaPaint.cpp
@@ -141,7 +141,7 @@ String RichObjectImageMaker::Key() const
 	RawCat(b, object.GetSerialId());
 	RawCat(b, sz);
 	RawCat(b, context);
-	return b;
+	return String(b);
 }
 
 Image RichObjectImageMaker::Make() const
diff --git a/uppsrc/Sql/SqlCode.cpp b/uppsrc/Sql/SqlCode.cpp
index db2b94daa..c170e3cde 100644
--- a/uppsrc/Sql/SqlCode.cpp
+++ b/uppsrc/Sql/SqlCode.cpp
@@ -10,7 +10,7 @@ String MakeSqlValue(int code, T& value)
 	StringBuffer b(sizeof(T) + 1);
 	b[0] = code;
 	memcpy(~b + 1, &value, sizeof(T));
-	return b;
+	return String(b);
 }
 
 template <class T>
@@ -327,7 +327,7 @@ String SqlCompile(byte dialect, const String& s)
 	b.Reserve(s.GetLength() + 100);
 	const char *q = s;
 	SqlCompile(q, &b, dialect, NULL);
-	return b;
+	return String(b);
 }
 
 #ifndef NOAPPSQL
@@ -370,7 +370,7 @@ String SqlFormat0(const char *s, int l, int code)
 	b[0] = code;
 	memcpy(~b + 1, &l, sizeof(int));
 	memcpy(~b + 1 + sizeof(int), s, l);
-	return b;
+	return String(b);
 }
 
 String SqlFormat(const char *s, int l)
diff --git a/uppsrc/Sql/SqlSet.cpp b/uppsrc/Sql/SqlSet.cpp
index 0869599c8..430dcaa11 100644
--- a/uppsrc/Sql/SqlSet.cpp
+++ b/uppsrc/Sql/SqlSet.cpp
@@ -48,7 +48,7 @@ String SqlSet::operator()(int at, byte cond) const {
 		return text;
 	StringBuffer out;
 	out << SqlCode(cond, "(")() << text << SqlCode(cond, ")")();
-	return out;
+	return String(out);
 }
 
 SqlSet& SqlSet::Cat(const SqlVal& val) {
diff --git a/uppsrc/Sql/SqlVal.cpp b/uppsrc/Sql/SqlVal.cpp
index 3a8e320e2..f89895830 100644
--- a/uppsrc/Sql/SqlVal.cpp
+++ b/uppsrc/Sql/SqlVal.cpp
@@ -77,7 +77,7 @@ String SqlS::operator()(int at, byte cond) const
 		return text;
 	StringBuffer out;
 	out << SqlCode(cond, "(")() << text << SqlCode(cond, ")")();
-	return out;
+	return String(out);
 }
 
 void SqlS::Init(const SqlS& a, const char *o, int olen, const SqlS& b, int pr, int prb)
diff --git a/uppsrc/ide/Browser/CodeRef.cpp b/uppsrc/ide/Browser/CodeRef.cpp
index 0ccaaf349..f70d1d7b0 100644
--- a/uppsrc/ide/Browser/CodeRef.cpp
+++ b/uppsrc/ide/Browser/CodeRef.cpp
@@ -158,7 +158,7 @@ String NaturalDeQtf(const char *s) {
 		}
 		s++;
 	}
-	return r;
+	return String(r);
 }
 
 static int sSplitT(int c) {
diff --git a/uppsrc/ide/Browser/File.cpp b/uppsrc/ide/Browser/File.cpp
index 0e97ebe9d..71fbf509a 100644
--- a/uppsrc/ide/Browser/File.cpp
+++ b/uppsrc/ide/Browser/File.cpp
@@ -97,7 +97,7 @@ String WriteTopic(const char *title, const RichText& text)
 	StringBuffer r;
 	r << "topic " << AsCString(title) << ";\r\n";
 	r << AsQTF(text, CHARSET_UTF8, QTF_BODY|QTF_ALL_STYLES|QTF_CRLF);
-	return r;
+	return String(r);
 }
 
 String WriteTopicI(const char *title, const RichText& text)
@@ -121,7 +121,7 @@ String WriteTopicI(const char *title, const RichText& text)
 			r << "\r\n";
 	}
 	r << "\r\n\r\n";
-	return r;
+	return String(r);
 }
 
 void SaveGroupInc(const String& grouppath)
diff --git a/uppsrc/ide/Core/Core.cpp b/uppsrc/ide/Core/Core.cpp
index 3f494b168..bd866cde0 100644
--- a/uppsrc/ide/Core/Core.cpp
+++ b/uppsrc/ide/Core/Core.cpp
@@ -532,7 +532,7 @@ String BrcToC(CParser& binscript, String basedir)
 			"int " << ident << "_length = " << b_length << ";\n\n";
 		}
 	}
-	return fo;
+	return String(fo);
 }
 
 void CopyFile(const String& d, const String& s, bool brc)
diff --git a/uppsrc/ide/Core/Package.cpp b/uppsrc/ide/Core/Package.cpp
index e05db8f9b..2b83dc836 100644
--- a/uppsrc/ide/Core/Package.cpp
+++ b/uppsrc/ide/Core/Package.cpp
@@ -14,7 +14,7 @@ String ReadValue(CParser& p)
 	while(IsUppValueChar(p.PeekChar()))
 		v.Cat(p.GetChar());
 	p.Spaces();
-	return v;
+	return String(v);
 }
 
 static bool sMatchOr(CParser& p, const Vector<String>& flag);
diff --git a/uppsrc/ide/idetool.cpp b/uppsrc/ide/idetool.cpp
index 79cdc7dd7..512b3d2f9 100644
--- a/uppsrc/ide/idetool.cpp
+++ b/uppsrc/ide/idetool.cpp
@@ -325,7 +325,7 @@ static WString sSwapCase(const WString& s)
 	r.SetCount(s.GetCount());
 	for(int i = 0; i < s.GetCount(); i++)
 		r[i] = IsUpper(s[i]) ? ToLower(s[i]) : ToUpper(s[i]);
-	return r;
+	return WString(r);
 }
 
 void Ide::SwapCase()
diff --git a/uppsrc/plugin/bmp/Icon.cpp b/uppsrc/plugin/bmp/Icon.cpp
index 4206e91b0..db5277542 100644
--- a/uppsrc/plugin/bmp/Icon.cpp
+++ b/uppsrc/plugin/bmp/Icon.cpp
@@ -216,7 +216,7 @@ String WriteIcon(const Vector<Image>& icons, int flags)
 			Poke32le(entry + OFFSETOF(BMP_ICONDIRENTRY, dwImageOffset), out_offset);
 		}
 	}
-	return out;
+	return String(out);
 }
 
 }