# Handle 'O' time zone skeleton in DateIntervalFormat.
# Keep time zone skeleton field widths in DateIntervalFormat.
#
# ICU bug: https://unicode-org.atlassian.net/browse/ICU-20548

diff --git a/intl/icu/source/i18n/dtitv_impl.h b/intl/icu/source/i18n/dtitv_impl.h
--- a/intl/icu/source/i18n/dtitv_impl.h
+++ b/intl/icu/source/i18n/dtitv_impl.h
@@ -84,16 +84,19 @@
 #define CAP_W             ((char16_t)0x0057)
 #define CAP_Y             ((char16_t)0x0059)
 #define CAP_Z             ((char16_t)0x005A)
 
 //#define MINIMUM_SUPPORTED_CALENDAR_FIELD    UCAL_MINUTE
 
 #define MAX_E_COUNT      5
 #define MAX_M_COUNT      5
+#define MAX_z_COUNT      4
+#define MAX_v_COUNT      4
+#define MAX_O_COUNT      4
 //#define MAX_INTERVAL_INDEX 4
 #define MAX_POSITIVE_INT  56632
 
 
 #endif /* #if !UCONFIG_NO_FORMATTING */
 
 #endif 
 //eof
diff --git a/intl/icu/source/i18n/dtitvfmt.cpp b/intl/icu/source/i18n/dtitvfmt.cpp
--- a/intl/icu/source/i18n/dtitvfmt.cpp
+++ b/intl/icu/source/i18n/dtitvfmt.cpp
@@ -1061,16 +1061,17 @@ DateIntervalFormat::getDateTimeSkeleton(
     // timeSkeleton follows the sequence of hm*[v|z]?
     int32_t ECount = 0;
     int32_t dCount = 0;
     int32_t MCount = 0;
     int32_t yCount = 0;
     int32_t mCount = 0;
     int32_t vCount = 0;
     int32_t zCount = 0;
+    int32_t OCount = 0;
     char16_t hourChar = u'\0';
     int32_t i;
 
     for (i = 0; i < skeleton.length(); ++i) {
         char16_t ch = skeleton[i];
         switch ( ch ) {
           case CAP_E:
             dateSkeleton.append(ch);
@@ -1123,16 +1124,20 @@ DateIntervalFormat::getDateTimeSkeleton(
           case LOW_Z:
             ++zCount;
             timeSkeleton.append(ch);
             break;
           case LOW_V:
             ++vCount;
             timeSkeleton.append(ch);
             break;
+          case CAP_O:
+            ++OCount;
+            timeSkeleton.append(ch);
+            break;
           case LOW_A:
           case CAP_V:
           case CAP_Z:
           case LOW_J:
           case LOW_S:
           case CAP_S:
           case CAP_A:
           case LOW_B:
@@ -1174,20 +1179,41 @@ DateIntervalFormat::getDateTimeSkeleton(
     /* generate normalized form for time */
     if ( hourChar != u'\0' ) {
         normalizedTimeSkeleton.append(hourChar);
     }
     if ( mCount != 0 ) {
         normalizedTimeSkeleton.append(LOW_M);
     }
     if ( zCount != 0 ) {
-        normalizedTimeSkeleton.append(LOW_Z);
+        if ( zCount <= 3 ) {
+            normalizedTimeSkeleton.append(LOW_Z);
+        } else {
+            for ( int32_t j = 0; j < zCount && j < MAX_z_COUNT; ++j ) {
+                 normalizedTimeSkeleton.append(LOW_Z);
+            }
+        }
     }
     if ( vCount != 0 ) {
-        normalizedTimeSkeleton.append(LOW_V);
+        if ( vCount <= 3 ) {
+            normalizedTimeSkeleton.append(LOW_V);
+        } else {
+            for ( int32_t j = 0; j < vCount && j < MAX_v_COUNT; ++j ) {
+                 normalizedTimeSkeleton.append(LOW_V);
+            }
+        }
+    }
+    if ( OCount != 0 ) {
+        if ( OCount <= 3 ) {
+            normalizedTimeSkeleton.append(CAP_O);
+        } else {
+            for ( int32_t j = 0; j < OCount && j < MAX_O_COUNT; ++j ) {
+                 normalizedTimeSkeleton.append(CAP_O);
+            }
+        }
     }
 }
 
 
 /**
  * Generate date or time interval pattern from resource,
  * and set them into the interval pattern locale to this formatter.
  *
@@ -1732,18 +1758,23 @@ DateIntervalFormat::adjustFieldWidth(con
         findReplaceInPattern(adjustedPtn, UnicodeString(u"a\u202F",-1), UnicodeString());
         findReplaceInPattern(adjustedPtn, UnicodeString(LOW_A), UnicodeString());
         // adjust interior double spaces, remove exterior whitespace
         findReplaceInPattern(adjustedPtn, UnicodeString("  "), UnicodeString(" "));
         adjustedPtn.trim();
     }
     if ( differenceInfo == 2 ) {
         if (inputSkeleton.indexOf(LOW_Z) != -1) {
+             bestMatchSkeletonFieldWidth[(int)(LOW_Z - PATTERN_CHAR_BASE)] = bestMatchSkeletonFieldWidth[(int)(LOW_V - PATTERN_CHAR_BASE)];
              findReplaceInPattern(adjustedPtn, UnicodeString(LOW_V), UnicodeString(LOW_Z));
          }
+         if (inputSkeleton.indexOf(CAP_O) != -1) {
+             bestMatchSkeletonFieldWidth[(int)(CAP_O - PATTERN_CHAR_BASE)] = bestMatchSkeletonFieldWidth[(int)(LOW_V - PATTERN_CHAR_BASE)];
+             findReplaceInPattern(adjustedPtn, UnicodeString(LOW_V), UnicodeString(CAP_O));
+         }
          if (inputSkeleton.indexOf(CAP_K) != -1) {
              findReplaceInPattern(adjustedPtn, UnicodeString(LOW_H), UnicodeString(CAP_K));
          }
          if (inputSkeleton.indexOf(LOW_K) != -1) {
              findReplaceInPattern(adjustedPtn, UnicodeString(CAP_H), UnicodeString(LOW_K));
          }
          if (inputSkeleton.indexOf(LOW_B) != -1) {
              findReplaceInPattern(adjustedPtn, UnicodeString(LOW_A), UnicodeString(LOW_B));
diff --git a/intl/icu/source/i18n/dtitvinf.cpp b/intl/icu/source/i18n/dtitvinf.cpp
--- a/intl/icu/source/i18n/dtitvinf.cpp
+++ b/intl/icu/source/i18n/dtitvinf.cpp
@@ -582,19 +582,20 @@ DateIntervalInfo::getBestSkeleton(const 
 
     // hack for certain alternate characters
     // resource bundles only have time skeletons containing 'v', 'h', and 'H'
     // but not time skeletons containing 'z', 'K', or 'k'
     // the skeleton may also include 'a' or 'b', which never occur in the resource bundles, so strip them out too
     UBool replacedAlternateChars = false;
     const UnicodeString* inputSkeleton = &skeleton;
     UnicodeString copySkeleton;
-    if ( skeleton.indexOf(LOW_Z) != -1 || skeleton.indexOf(LOW_K) != -1 || skeleton.indexOf(CAP_K) != -1 || skeleton.indexOf(LOW_A) != -1 || skeleton.indexOf(LOW_B) != -1 ) {
+    if ( skeleton.indexOf(LOW_Z) != -1 || skeleton.indexOf(CAP_O) != -1 || skeleton.indexOf(LOW_K) != -1 || skeleton.indexOf(CAP_K) != -1 || skeleton.indexOf(LOW_A) != -1 || skeleton.indexOf(LOW_B) != -1 ) {
         copySkeleton = skeleton;
         copySkeleton.findAndReplace(UnicodeString(LOW_Z), UnicodeString(LOW_V));
+        copySkeleton.findAndReplace(UnicodeString(CAP_O), UnicodeString(LOW_V));
         copySkeleton.findAndReplace(UnicodeString(LOW_K), UnicodeString(CAP_H));
         copySkeleton.findAndReplace(UnicodeString(CAP_K), UnicodeString(LOW_H));
         copySkeleton.findAndReplace(UnicodeString(LOW_A), UnicodeString());
         copySkeleton.findAndReplace(UnicodeString(LOW_B), UnicodeString());
         inputSkeleton = &copySkeleton;
         replacedAlternateChars = true;
     }