Improve concat lint error & cleanups for future commit.

src/V3AstNodeExpr.h

@@ -1738,7 +1738,8 @@ class AstPatMember final : public AstNodeExpr {
     // @astgen op2 := keyp : Optional[AstNode]
     // @astgen op3 := repp : Optional[AstNodeExpr]  // replication count, or nullptr for count 1
     // @astgen op4 := varrefp : Optional[AstNodeExpr]  // Decoded variable if TEXT
-    bool m_default = false;
+    bool m_isDefault = false;  // Has default
+    bool m_isConcat = false;  // From concatenate
 
 public:
     AstPatMember(FileLine* fl, AstNodeExpr* lhssp, AstNode* keyp, AstNodeExpr* repp)
@@ -1755,8 +1756,10 @@ public:
     int instrCount() const override { return widthInstrs() * 2; }
     void dump(std::ostream& str = std::cout) const override;
     void dumpJson(std::ostream& str = std::cout) const override;
-    bool isDefault() const { return m_default; }
+    bool isConcat() const { return m_isConcat; }
-    void isDefault(bool flag) { m_default = flag; }
+    void isConcat(bool flag) { m_isConcat = flag; }
+    bool isDefault() const { return m_isDefault; }
+    void isDefault(bool flag) { m_isDefault = flag; }
 };
 class AstPattern final : public AstNodeExpr {
     // Verilog '{a,b,c,d...}

src/V3AstNodes.cpp

@@ -2263,9 +2263,11 @@ void AstPackageImport::pkgNameFrom() {
 }
 void AstPatMember::dump(std::ostream& str) const {
     this->AstNodeExpr::dump(str);
+    if (isConcat()) str << " [CONCAT]";
     if (isDefault()) str << " [DEFAULT]";
 }
 void AstPatMember::dumpJson(std::ostream& str) const {
+    if (isConcat()) dumpJsonBoolFunc(str, isConcat);
     if (isDefault()) dumpJsonBoolFunc(str, isDefault);
     dumpJsonGen(str);
 }

src/V3Width.cpp

@@ -573,7 +573,6 @@ class WidthVisitor final : public VNVisitor {
             // to determine if value or push
             userIterateAndNext(nodep->lhsp(), WidthVP{vdtypep, PRELIM}.p());
             userIterateAndNext(nodep->rhsp(), WidthVP{vdtypep, PRELIM}.p());
-            // Queue "element 0" is lhsp, so we need to swap arguments
             const bool lhsIsValue
                 = AstNode::computeCastable(adtypep->subDTypep(), nodep->lhsp()->dtypep(), nullptr)
                       .isAssignable();
@@ -4537,6 +4536,7 @@ class WidthVisitor final : public VNVisitor {
         UINFO(9, "ent " << range.left() << " to " << range.right() << endl);
         AstNode* newp = nullptr;
         bool allConstant = true;
+        const bool isConcat = nodep->itemsp() && VN_AS(nodep->itemsp(), PatMember)->isConcat();
         for (int entn = 0, ent = range.left(); entn < range.elements();
              ++entn, ent += range.leftToRightInc()) {
             AstPatMember* newpatp = nullptr;
@@ -4546,10 +4546,10 @@ class WidthVisitor final : public VNVisitor {
                 if (defaultp) {
                     newpatp = defaultp->cloneTree(false);
                     patp = newpatp;
-                } else if (!(VN_IS(arrayDtp, UnpackArrayDType) && !allConstant)) {
+                } else if (!(VN_IS(arrayDtp, UnpackArrayDType) && !allConstant && isConcat)) {
                     // If arrayDtp is an unpacked array and item is not constant,
-                    // the number of elemnt cannot be determined here as the dtype of each element
+                    // the number of elements cannot be determined here as the dtype of each
-                    // is not set yet. V3Slice checks for such cases.
+                    // element is not set yet. V3Slice checks for such cases.
                     nodep->v3error("Assignment pattern missed initializing elements: " << ent);
                 }
             } else {
@@ -7855,14 +7855,18 @@ class WidthVisitor final : public VNVisitor {
         if (AstConcat* lhsp = VN_CAST(nodep->lhsp(), Concat)) {
             patConcatConvertRecurse(patternp, lhsp);
         } else {
-            patternp->addItemsp(new AstPatMember{nodep->lhsp()->fileline(),
+            AstPatMember* const newp = new AstPatMember{
-                                                 nodep->lhsp()->unlinkFrBack(), nullptr, nullptr});
+                nodep->lhsp()->fileline(), nodep->lhsp()->unlinkFrBack(), nullptr, nullptr};
+            newp->isConcat(true);
+            patternp->addItemsp(newp);
         }
         if (AstConcat* rhsp = VN_CAST(nodep->rhsp(), Concat)) {
             patConcatConvertRecurse(patternp, rhsp);
         } else {
-            patternp->addItemsp(new AstPatMember{nodep->rhsp()->fileline(),
+            AstPatMember* const newp = new AstPatMember{
-                                                 nodep->rhsp()->unlinkFrBack(), nullptr, nullptr});
+                nodep->rhsp()->fileline(), nodep->rhsp()->unlinkFrBack(), nullptr, nullptr};
+            newp->isConcat(true);
+            patternp->addItemsp(newp);
         }
     }
 

test_regress/t/t_unpacked_concat_bad.out

@@ -3,4 +3,8 @@
    12 |    localparam bit_int_t count_bits [1:0] = {2{$bits(count_t)}};
       |                                              ^
                     ... For error description see https://verilator.org/warn/UNSUPPORTED?v=latest
+%Error: t/t_unpacked_concat_bad.v:12:46: Assignment pattern missed initializing elements: 0
+                                       : ... note: In instance 't'
+   12 |    localparam bit_int_t count_bits [1:0] = {2{$bits(count_t)}};
+      |                                              ^
 %Error: Exiting due to

test_regress/t/t_unpacked_concat_bad3.out

@@ -1,4 +1,9 @@
-%Error: Internal Error: t/t_unpacked_concat_bad3.v:9:41: ../V3EmitCConstInit.h:#: Missing array init element
+%Error: t/t_unpacked_concat_bad3.v:9:41: Assignment pattern missed initializing elements: 3
+                                       : ... note: In instance 't'
     9 |    localparam logic [7:0] TOO_FEW [5] = '{0, 1, 2**8-1};   
       |                                         ^~
-                        ... See the manual at https://verilator.org/verilator_doc.html for more assistance.
+%Error: t/t_unpacked_concat_bad3.v:9:41: Assignment pattern missed initializing elements: 4
+                                       : ... note: In instance 't'
+    9 |    localparam logic [7:0] TOO_FEW [5] = '{0, 1, 2**8-1};   
+      |                                         ^~
+%Error: Exiting due to