--- source/common/rbbidata.h
+++ source/common/rbbidata.h
@@ -113,7 +113,7 @@
                                     /*     StatusTable of the set of matching             */
                                     /*     tags (rule status values)                      */
     int16_t          fReserved;
-    uint16_t         fNextState[2]; /*  Next State, indexed by char category.             */
+    uint16_t         fNextState[1]; /*  Next State, indexed by char category.             */
                                     /*  This array does not have two elements             */
                                     /*    Array Size is actually fData->fHeader->fCatCount         */
                                     /*    CAUTION:  see RBBITableBuilder::getTableSize()  */
@@ -126,7 +126,7 @@
     uint32_t         fRowLen;       /*  Length of a state table row, in bytes.            */
     uint32_t         fFlags;        /*  Option Flags for this state table                 */
     uint32_t         fReserved;     /*  reserved                                          */
-    char             fTableData[4]; /*  First RBBIStateTableRow begins here.              */
+    char             fTableData[1]; /*  First RBBIStateTableRow begins here.              */
                                     /*    (making it char[] simplifies ugly address       */
                                     /*     arithmetic for indexing variable length rows.) */
 };
--- source/common/rbbitblb.cpp
+++ source/common/rbbitblb.cpp
@@ -1067,15 +1067,15 @@
         return 0;
     }
 
-    size    = sizeof(RBBIStateTable) - 4;    // The header, with no rows to the table.
+    size    = offsetof(RBBIStateTable, fTableData);    // The header, with no rows to the table.
 
     numRows = fDStates->size();
     numCols = fRB->fSetBuilder->getNumCharCategories();
 
-    //  Note  The declaration of RBBIStateTableRow is for a table of two columns.
-    //        Therefore we subtract two from numCols when determining
+    //  Note  The declaration of RBBIStateTableRow is for a table of one columns.
+    //        Therefore we subtract one from numCols when determining
     //        how much storage to add to a row for the total columns.
-    rowSize = sizeof(RBBIStateTableRow) + sizeof(uint16_t)*(numCols-2);
+    rowSize = sizeof(RBBIStateTableRow) + sizeof(uint16_t)*(numCols-1);
     size   += numRows * rowSize;
     return size;
 }
@@ -1105,7 +1105,7 @@
     }
 
     table->fRowLen    = sizeof(RBBIStateTableRow) +
-                            sizeof(uint16_t) * (fRB->fSetBuilder->getNumCharCategories() - 2);
+                            sizeof(uint16_t) * (fRB->fSetBuilder->getNumCharCategories() - 1);
     table->fNumStates = fDStates->size();
     table->fFlags     = 0;
     if (fRB->fLookAheadHardBreak) {
--- source/common/ucharstriebuilder.cpp
+++ source/common/ucharstriebuilder.cpp
@@ -285,7 +285,7 @@
 
 UCharsTrieBuilder::UCTLinearMatchNode::UCTLinearMatchNode(const UChar *units, int32_t len, Node *nextNode)
         : LinearMatchNode(len, nextNode), s(units) {
-    hash=hash*37+ustr_hashUCharsN(units, len);
+    hash=hash*37U+ustr_hashUCharsN(units, len);
 }
 
 UBool
--- source/common/ucmndata.h
+++ source/common/ucmndata.h
@@ -50,7 +50,7 @@
 
 typedef struct {
     uint32_t count;
-    UDataOffsetTOCEntry entry[2];    /* Actual size of array is from count. */
+    UDataOffsetTOCEntry entry[1];    /* Actual size of array is from count. */
 } UDataOffsetTOC;
 
 /**
--- source/common/unicode/stringtriebuilder.h
+++ source/common/unicode/stringtriebuilder.h
@@ -269,7 +269,7 @@
         void setValue(int32_t v) {
             hasValue=TRUE;
             value=v;
-            hash=hash*37+v;
+            hash=hash*37U+v;
         }
     protected:
         UBool hasValue;
@@ -296,7 +296,7 @@
     class LinearMatchNode : public ValueNode {
     public:
         LinearMatchNode(int32_t len, Node *nextNode)
-                : ValueNode((0x333333*37+len)*37+hashCode(nextNode)),
+                : ValueNode((0x333333U*37+len)*37+hashCode(nextNode)),
                   length(len), next(nextNode) {}
         virtual UBool operator==(const Node &other) const;
         virtual int32_t markRightEdgesFirst(int32_t edgeNumber);
@@ -330,7 +330,7 @@
             equal[length]=NULL;
             values[length]=value;
             ++length;
-            hash=(hash*37+c)*37+value;
+            hash=(hash*37U+c)*37+value;
         }
         // Adds a unit which leads to another match node.
         void add(int32_t c, Node *node) {
@@ -338,7 +338,7 @@
             equal[length]=node;
             values[length]=0;
             ++length;
-            hash=(hash*37+c)*37+hashCode(node);
+            hash=(hash*37U+c)*37+hashCode(node);
         }
     protected:
         Node *equal[kMaxBranchLinearSubNodeLength];  // NULL means "has final value".
@@ -353,7 +353,7 @@
     class SplitBranchNode : public BranchNode {
     public:
         SplitBranchNode(UChar middleUnit, Node *lessThanNode, Node *greaterOrEqualNode)
-                : BranchNode(((0x555555*37+middleUnit)*37+
+                : BranchNode(((0x555555U*37+middleUnit)*37+
                               hashCode(lessThanNode))*37+hashCode(greaterOrEqualNode)),
                   unit(middleUnit), lessThan(lessThanNode), greaterOrEqual(greaterOrEqualNode) {}
         virtual UBool operator==(const Node &other) const;
@@ -370,7 +370,7 @@
     class BranchHeadNode : public ValueNode {
     public:
         BranchHeadNode(int32_t len, Node *subNode)
-                : ValueNode((0x666666*37+len)*37+hashCode(subNode)),
+                : ValueNode((0x666666U*37+len)*37+hashCode(subNode)),
                   length(len), next(subNode) {}
         virtual UBool operator==(const Node &other) const;
         virtual int32_t markRightEdgesFirst(int32_t edgeNumber);
--- source/common/uresbund.cpp
+++ source/common/uresbund.cpp
@@ -53,7 +53,7 @@
     UHashTok namekey, pathkey;
     namekey.pointer = b->fName;
     pathkey.pointer = b->fPath;
-    return uhash_hashChars(namekey)+37*uhash_hashChars(pathkey);
+    return uhash_hashChars(namekey)+37U*uhash_hashChars(pathkey);
 }
 
 /* INTERNAL: compares two entries */
--- source/common/ustring.cpp
+++ source/common/ustring.cpp
@@ -1486,7 +1486,7 @@
 */
 
 #define STRING_HASH(TYPE, STR, STRLEN, DEREF) \
-    int32_t hash = 0;                         \
+    uint32_t hash = 0;                         \
     const TYPE *p = (const TYPE*) STR;        \
     if (p != NULL) {                          \
         int32_t len = (int32_t)(STRLEN);      \
@@ -1497,7 +1497,7 @@
             p += inc;                         \
         }                                     \
     }                                         \
-    return hash
+    return static_cast<int32_t>(hash)
 
 /* Used by UnicodeString to compute its hashcode - Not public API. */
 U_CAPI int32_t U_EXPORT2