Fix false warnings on non-power-2 enums using .next/.prev.

Changes

@@ -6,6 +6,9 @@ indicates the contributor was also the author of the fix; Thanks!
 
 * Verilator 3.885 devel
 
+****  Fix false warnings on non-power-2 enums using .next/.prev.
+
+
 * Verilator 3.884 2016-05-18
 
 **    Support parameter type, bug376. [Alan Hunter, et al]

src/V3Width.cpp

@@ -1493,6 +1493,7 @@ private:
 		    nodep->v3error("Unsupported: Arguments passed to enum.next method");
 		}
 		// Need a runtime lookup table.  Yuk.
+		// Most enums unless overridden are 32 bits, so we size array based on max enum value used.
 		// Ideally we would have a fast algorithm when a number is
 		// of small width and complete and so can use an array, and
 		// a map for when the value is many bits and sparse.
@@ -1508,10 +1509,15 @@ private:
 			return;
 		    }
 		}
+		int selwidth = V3Number::log2b(msbdim)+1;	// Width to address a bit
 		AstVar* varp = enumVarp(adtypep, attrType, msbdim);
 		AstVarRef* varrefp = new AstVarRef(nodep->fileline(), varp, false);
 		varrefp->packagep(v3Global.rootp()->dollarUnitPkgAddp());
-		AstNode* newp = new AstArraySel(nodep->fileline(), varrefp, nodep->fromp()->unlinkFrBack());
+		AstNode* newp = new AstArraySel(nodep->fileline(), varrefp,
+						// Select in case widths are off due to msblen!=width
+						new AstSel(nodep->fileline(),
+							   nodep->fromp()->unlinkFrBack(),
+							   0, selwidth));
 		nodep->replaceWith(newp); nodep->deleteTree(); VL_DANGLING(nodep);
 	    } else {
 		nodep->v3error("Unknown built-in enum method '"<<nodep->fromp()->prettyTypeName()<<"'");
@@ -3413,7 +3419,7 @@ private:
     }
     AstVar* enumVarp(AstEnumDType* nodep, AstAttrType attrType, uint32_t msbdim) {
 	// Return a variable table which has specified dimension properties for this variable
-	TableMap::iterator pos = m_tableMap.find(make_pair(nodep,attrType));
+	TableMap::iterator pos = m_tableMap.find(make_pair(nodep, attrType));
 	if (pos != m_tableMap.end()) {
 	    return pos->second;
 	}
@@ -3422,7 +3428,7 @@ private:
 	if (attrType == AstAttrType::ENUM_NAME) {
 	    basep = nodep->findStringDType();
 	} else {
-	    basep = nodep->findSigned32DType();
+	    basep = nodep->dtypep();
 	}
 	AstNodeArrayDType* vardtypep = new AstUnpackArrayDType(nodep->fileline(),
 							       basep,

test_regress/t/t_enum_type_methods.v

@@ -12,11 +12,11 @@ module t (/*AUTOARG*/
    );
    input clk;
 
-   typedef enum {
-		 E01 = 1,
-		 E03 = 3,
-		 E04 = 4
-		 } my_t;
+   typedef enum [3:0] {
+		       E01 = 1,
+		       E03 = 3,
+		       E04 = 4
+		       } my_t;
 
    integer 	cyc=0;
    my_t e;