From a5fa468343296e0b3fb7c5cebfede9e7e3588555 Mon Sep 17 00:00:00 2001
From: Wilson Snyder <wsnyder@wsnyder.org>
Date: Thu, 10 Dec 2020 18:36:06 -0500
Subject: [PATCH] Fix cast from packed structs, broke with $cast (#2684)

---
 src/V3Width.cpp         |  8 ++++----
 test_regress/t/t_cast.v | 17 +++++++++++++++++
 2 files changed, 21 insertions(+), 4 deletions(-)

diff --git a/src/V3Width.cpp b/src/V3Width.cpp
index 188241d8c..4cfa81dd6 100644
--- a/src/V3Width.cpp
+++ b/src/V3Width.cpp
@@ -5990,13 +5990,13 @@ private:
         toDtp = toDtp->skipRefToEnump();
         fromDtp = fromDtp->skipRefToEnump();
         if (toDtp == fromDtp) return COMPATIBLE;
+        bool fromNumericable = VN_IS(fromDtp, BasicDType) || VN_IS(fromDtp, EnumDType)
+                               || VN_IS(fromDtp, NodeUOrStructDType);
         // UNSUP unpacked struct/unions (treated like BasicDType)
         if (VN_IS(toDtp, BasicDType) || VN_IS(toDtp, NodeUOrStructDType)) {
-            if (VN_IS(fromDtp, BasicDType)) return COMPATIBLE;
-            if (VN_IS(fromDtp, EnumDType)) return COMPATIBLE;
-            if (VN_IS(fromDtp, NodeUOrStructDType)) return COMPATIBLE;
+            if (fromNumericable) return COMPATIBLE;
         } else if (VN_IS(toDtp, EnumDType)) {
-            if (VN_IS(fromDtp, BasicDType) || VN_IS(fromDtp, EnumDType)) return DYNAMIC_ENUM;
+            if (fromNumericable) return DYNAMIC_ENUM;
         } else if (VN_IS(toDtp, ClassRefDType) && VN_IS(fromConstp, Const)) {
             if (VN_IS(fromConstp, Const) && VN_CAST(fromConstp, Const)->num().isNull())
                 return COMPATIBLE;
diff --git a/test_regress/t/t_cast.v b/test_regress/t/t_cast.v
index baccee871..b41caa110 100644
--- a/test_regress/t/t_cast.v
+++ b/test_regress/t/t_cast.v
@@ -13,12 +13,18 @@ module t;
       logic [15:0] data;
    } packed_t;
 
+   typedef enum [15:0] {
+      ONE = 1
+   } enum_t;
+
    packed_t pdata;
+   packed_t pdata_reg;
    assign pdata.data = 16'h1234;
    logic [7:0] logic8bit;
    assign logic8bit = $bits(logic8bit)'(pdata >> 8);
 
    mc_t o;
+   enum_t e;
 
    logic [15:0] allones = 16'hffff;
    parameter FOUR = 4;
@@ -55,6 +61,17 @@ module t;
       if ((FOUR+2)'(allones) !== 6'h3f) $stop;
       if (50 !== RESULT) $stop;
 
+      e = ONE;
+      if (e != 1) $stop;
+      if (e != ONE) $stop;
+      e = enum_t'(ONE);
+      if (e != ONE) $stop;
+      e = enum_t'(16'h1);
+      if (e != ONE) $stop;
+      pdata_reg.data = 1;
+      e = enum_t'(pdata_reg);
+      if (e != ONE) $stop;
+
       o = tocast_t'(4'b1);
       if (o != 4'b1) $stop;