patches/ucase_utf8.patch

diff --git a/source/common/ucase.cpp b/source/common/ucase.cpp
index 706d7289..6b22f9e3 100644
--- a/source/common/ucase.cpp
+++ b/source/common/ucase.cpp
@@ -961,6 +961,7 @@ ucase_toFullLower(UChar32 c,
                     0307; ; 0307; 0307; tr After_I; # COMBINING DOT ABOVE
                     0307; ; 0307; 0307; az After_I; # COMBINING DOT ABOVE
                  */
+                *pString=nullptr;
                 return 0; /* remove the dot (continue without output) */
             } else if(loc==UCASE_LOC_TURKISH && c==0x49 && !isFollowedByDotAbove(iter, context)) {
                 /*
@@ -1059,6 +1060,7 @@ toUpperOrTitle(UChar32 c,
 
                     0307; 0307; ; ; lt After_Soft_Dotted; # COMBINING DOT ABOVE
                  */
+                *pString=nullptr;
                 return 0; /* remove the dot (continue without output) */
             } else {
                 /* no known conditional special case mapping, use a normal mapping */
diff --git a/source/common/ucasemap.cpp b/source/common/ucasemap.cpp
index 391140d6..1523cb6d 100644
--- a/source/common/ucasemap.cpp
+++ b/source/common/ucasemap.cpp
@@ -177,18 +177,22 @@ appendResult(uint8_t *dest, int32_t destIndex, int32_t destCapacity,
     } else {
         if(result<=UCASE_MAX_STRING_LENGTH) {
             // string: "result" is the UTF-16 length
-            errorCode=U_ZERO_ERROR;
-            if(destIndex<destCapacity) {
-                u_strToUTF8((char *)(dest+destIndex), destCapacity-destIndex, &length,
-                            s, result, &errorCode);
+            if(result==0) {
+                length=0;
             } else {
-                u_strToUTF8(NULL, 0, &length, s, result, &errorCode);
-            }
-            if(U_FAILURE(errorCode) && errorCode != U_BUFFER_OVERFLOW_ERROR) {
-                return -1;
-            }
-            if(length>(INT32_MAX-destIndex)) {
-                return -1;  // integer overflow
+                errorCode=U_ZERO_ERROR;
+                if(destIndex<destCapacity) {
+                    u_strToUTF8((char *)(dest+destIndex), destCapacity-destIndex, &length,
+                                s, result, &errorCode);
+                } else {
+                    u_strToUTF8(NULL, 0, &length, s, result, &errorCode);
+                }
+                if(U_FAILURE(errorCode) && errorCode != U_BUFFER_OVERFLOW_ERROR) {
+                    return -1;
+                }
+                if(length>(INT32_MAX-destIndex)) {
+                    return -1;  // integer overflow
+                }
             }
             if(edits!=NULL) {
                 edits->addReplace(cpLength, length);