Internals: Enforce types on C++ enums. No functional change intended.

include/verilated.h

@@ -140,7 +140,7 @@ enum VerilatedVarType : uint8_t {
     VLVT_REAL  // AKA double
 };
 
-enum VerilatedVarFlags {
+enum VerilatedVarFlags : uint32_t {
     VLVD_0 = 0,  // None
     VLVD_IN = 1,  // == vpiInput
     VLVD_OUT = 2,  // == vpiOutput

src/V3AstNodeExpr.h

@@ -5329,7 +5329,7 @@ public:
 class AstAtoN final : public AstNodeUniop {
     // string.atoi(), atobin(), atohex(), atooct(), atoireal()
 public:
-    enum FmtType { ATOI = 10, ATOHEX = 16, ATOOCT = 8, ATOBIN = 2, ATOREAL = -1 };
+    enum FmtType : int { ATOI = 10, ATOHEX = 16, ATOOCT = 8, ATOBIN = 2, ATOREAL = -1 };
 
 private:
     const FmtType m_fmt;  // Operation type

src/V3AstNodeStmt.h

@@ -1455,7 +1455,7 @@ public:
     };
 
 private:
-    enum operation m_operation;
+    operation m_operation;
 
 public:
     AstAssignCompound(AstAssignCompound::operation operation, FileLine* fl, AstNodeExpr* lhsp,

src/V3Control.h

@@ -38,7 +38,7 @@ public:
         string resetValue;
     };
 
-    enum class VarSpecKind {
+    enum class VarSpecKind : uint8_t {
         PARAM,  // Select only matching parameters
         PORT,  // Select only matching ports
         VAR  // Select any matching AstVar (including params and ports)

src/V3EmitCHeaders.cpp

@@ -279,12 +279,12 @@ class EmitCHeader final : public EmitCConstInit {
             emitUnpackedUOrSBody(sdtypep);
         }
     }
-    enum class AttributeType { Width, Dimension };
+    enum class AttributeType : uint8_t { WIDTH, DIMENSION };
     // Get member attribute based on type
     int getNodeAttribute(const AstMemberDType* itemp, AttributeType type) {
         const bool isArrayType = itemp->dtypep()->isNonPackedArray();
         switch (type) {
-        case AttributeType::Width: {
+        case AttributeType::WIDTH: {
             if (isArrayType) {
                 // For arrays, get innermost element width
                 const AstNodeDType* dtype = itemp->dtypep();
@@ -293,7 +293,7 @@ class EmitCHeader final : public EmitCConstInit {
             }
             return itemp->width();
         }
-        case AttributeType::Dimension: {
+        case AttributeType::DIMENSION: {
             // Return array dimension or 0 for non-arrays
             return isArrayType ? itemp->dtypep()->dimensions(true).second : 0;
         }
@@ -345,10 +345,10 @@ class EmitCHeader final : public EmitCConstInit {
             puts("};\n}\n");
 
             putns(sdtypep, "\nstd::vector<int> memberWidth(void) const {\n");
-            emitMemberVector<AttributeType::Width>(sdtypep);
+            emitMemberVector<AttributeType::WIDTH>(sdtypep);
 
             putns(sdtypep, "\nstd::vector<int> memberDimension(void) const {\n");
-            emitMemberVector<AttributeType::Dimension>(sdtypep);
+            emitMemberVector<AttributeType::DIMENSION>(sdtypep);
 
             needComma = false;
             putns(sdtypep, "\nauto memberIndices(void) const {\n");

src/V3ExecGraph.cpp

@@ -420,12 +420,10 @@ class PackThreads final {
         // schedule to ensure that indexes for simulation-time thread pool workers are not shadowed
         // by another tasks.
         // For retaining control over thread schedules, we distinguish SchedulingModes:
-        enum class SchedulingMode {
-            SCHEDULING  // Schedule normal tasks
-            ,
-            WIDE_TASK_DISCOVERED  // We found a wide task, if this is the only one available,
-                                  // switch to WIDE_TASK_SCHEDULING
-            ,
+        enum class SchedulingMode : uint8_t {
+            SCHEDULING,  // Schedule normal tasks
+            WIDE_TASK_DISCOVERED,  // Found a wide task, if this is the only one available,
+                                   // switch to WIDE_TASK_SCHEDULING
             WIDE_TASK_SCHEDULING  // Schedule wide tasks
         };
         SchedulingMode mode = SchedulingMode::SCHEDULING;

src/V3FileLine.h

@@ -53,7 +53,7 @@ class FileLineSingleton final {
         VErrorBitSet m_ctrlEn;  // Enabled by control file
 
     public:
-        enum class Subset {
+        enum class Subset : uint8_t {
             CODE = 0,  // Selects m_codeEn, the enable bits used by in-code directives/metacomments
             CTRL = 1,  // Selects m_ctrlEn, the enable bits used by control files
         };

src/V3LinkDotIfaceCapture.h

@@ -34,7 +34,7 @@ class VSymEnt;
 
 class V3LinkDotIfaceCapture final {
 public:
-    enum class CaptureType { IFACE, CLASS };
+    enum class CaptureType : uint8_t { IFACE, CLASS };
 
     // Path-based map key: no pointers, only stable strings.
     // {ownerModName, refName, cellPath, cloneCellPath} uniquely identifies

src/V3PreProc.h

@@ -40,7 +40,7 @@ protected:
 
 public:
     // CONSTANTS
-    enum MiscConsts {
+    enum MiscConsts : int {
         DEFINE_RECURSION_LEVEL_MAX = 1000,  // How many `def substitutions before an error
         INCLUDE_DEPTH_MAX = 500,  // How many `includes deep before an error
         // Streams deep (sometimes `def deep) before an error.

test_regress/t/t_dist_cppstyle.py

@@ -90,6 +90,14 @@ for filename in sorted(files.keys()):
         r'.*(Need \(\)|: m_e\()|V3OPTION_PARSER_DEF',
         "Use brace instead of parenthesis-style constructors e.g. ': m_...{...}'")
 
+    check_pattern(
+        filename,
+        contents,
+        r'\s*enum\s+(class\s+)?([a-zA-Z0-9_]+)',
+        # Ignore common m_e enum constructors
+        r' enum m_e | enum en | : [a-zA-Z]',
+        "Add type to enum declaration e.g. 'enum class foo : uint8_t'")
+
     if re.search(r'\.(c|cpp)', filename):
         check_pattern(filename, contents, r'(\w+\s+)*(\binline\b)[^\n]*', None,
                       "'inline' keyword is on functions defined in .cpp files")

test_regress/t/t_vpi_repetitive_cbs.cpp

@@ -35,7 +35,7 @@
 
 const std::vector<int> cbs_to_test{cbValueChange};
 
-enum CallbackState { PRE_REGISTER, ACTIVE, ACTIVE_AGAIN, REM_REREG_ACTIVE, POST_REMOVE };
+enum CallbackState : uint8_t { PRE_REGISTER, ACTIVE, ACTIVE_AGAIN, REM_REREG_ACTIVE, POST_REMOVE };
 const std::vector<CallbackState> cb_states{PRE_REGISTER, ACTIVE, ACTIVE_AGAIN, REM_REREG_ACTIVE,
                                            POST_REMOVE};