From 85e63e99a66e71c561aaf6b5fdb5d794bf89acf8 Mon Sep 17 00:00:00 2001
From: acqn <acqn163@outlook.com>
Date: Fri, 27 Oct 2023 21:51:45 +0800
Subject: [PATCH] Fixed regression: array element of incomplete type.

---
 src/cc65/compile.c   |  2 +-
 src/cc65/declare.c   | 34 ++++++++++++++++++----------------
 test/err/zero-size.c |  6 ++++++
 3 files changed, 25 insertions(+), 17 deletions(-)
 create mode 100644 test/err/zero-size.c

diff --git a/src/cc65/compile.c b/src/cc65/compile.c
index 9d7fbe20a..edd00022c 100644
--- a/src/cc65/compile.c
+++ b/src/cc65/compile.c
@@ -511,7 +511,7 @@ void Compile (const char* FileName)
 
                     /* Mark as defined; so that it will be exported, not imported */
                     Entry->Flags |= SC_DEF;
-                } else {
+                } else if (!IsTypeArray (Entry->Type)) {
                     /* Tentative declared variable is still of incomplete type */
                     Error ("Definition of '%s' has type '%s' that is never completed",
                            Entry->Name,
diff --git a/src/cc65/declare.c b/src/cc65/declare.c
index cd174c92d..cf9c13059 100644
--- a/src/cc65/declare.c
+++ b/src/cc65/declare.c
@@ -493,33 +493,35 @@ static void FixQualifiers (Type* DataType)
 
 
 
-static void CheckArrayElementType (Type* DataType)
+static void CheckArrayElementType (const Type* T)
 /* Check if data type consists of arrays of incomplete element types */
 {
-    Type* T = DataType;
-
     while (T->C != T_END) {
         if (IsTypeArray (T)) {
+            /* If the array is multi-dimensional, keep going until we get the
+            ** true element type.
+            */
             ++T;
-            if (IsIncompleteESUType (T)) {
-                /* We cannot have an array of incomplete elements */
-                Error ("Array of incomplete element type '%s'", GetFullTypeName (T));
-            } else if (SizeOf (T) == 0) {
-                /* If the array is multi-dimensional, try to get the true
-                ** element type.
-                */
-                if (IsTypeArray (T)) {
-                    continue;
-                }
-                /* We could support certain 0-size element types as an extension */
-                if (!IsTypeVoid (T) || IS_Get (&Standard) != STD_CC65) {
-                    Error ("Array of 0-size element type '%s'", GetFullTypeName (T));
+            if (SizeOf (T) == 0) {
+                if (IsTypeArray (T) || IsIncompleteESUType (T)) {
+                    /* We cannot have an array of incomplete elements */
+                    if (!IsTypeArray (T) || GetElementCount (T) == UNSPECIFIED) {
+                        Error ("Array of incomplete element type '%s'",
+                               GetFullTypeName (T));
+                        return;
+                    }
+                } else if (!IsTypeVoid (T) || IS_Get (&Standard) != STD_CC65) {
+                    /* We could support certain 0-size element types as an extension */
+                    Error ("Array of 0-size element type '%s'",
+                           GetFullTypeName (T));
+                    return;
                 }
             } else {
                 if (IsTypeStruct (T)) {
                     SymEntry* TagEntry = GetESUTagSym (T);
                     if (TagEntry && SymHasFlexibleArrayMember (TagEntry)) {
                         Error ("Invalid use of struct with flexible array member");
+                        return;
                     }
                 }
             }
diff --git a/test/err/zero-size.c b/test/err/zero-size.c
new file mode 100644
index 000000000..9e7510c91
--- /dev/null
+++ b/test/err/zero-size.c
@@ -0,0 +1,6 @@
+char a[][] = { 0, 0 }; /* Error: Array type has incomplete element type 'char[]' */
+
+int main(void)
+{
+    return 0;
+}