From 9c69aac09769810efe1ab92d748e2d93abcfaf19 Mon Sep 17 00:00:00 2001
From: Kugel Fuhr <98353208+kugelfuhr@users.noreply.github.com>
Date: Tue, 17 Sep 2024 11:45:46 +0200
Subject: [PATCH] Fix some issues with signedness in preprocessor expressions.
 Do also disallow comma expressions since the aren't compliant and collide
 with macro invocations.

---
 src/cc65/ppexpr.c  | 31 +++++++------------------------
 test/err/bug2523.c |  3 +++
 test/val/bug2523.c | 29 +++++++++++++++++++++++++++++
 3 files changed, 39 insertions(+), 24 deletions(-)
 create mode 100644 test/err/bug2523.c
 create mode 100644 test/val/bug2523.c

diff --git a/src/cc65/ppexpr.c b/src/cc65/ppexpr.c
index 8d8c0b65d..bedb01507 100644
--- a/src/cc65/ppexpr.c
+++ b/src/cc65/ppexpr.c
@@ -55,7 +55,6 @@ static int PPEvaluationFailed  = 0;
 
 
 
-static void PPhie0 (PPExpr* Expr);
 static void PPhie1 (PPExpr* Expr);
 
 
@@ -138,7 +137,7 @@ static void PPhiePrimary (PPExpr* Expr)
             ** recursively.
             */
             NextToken ();
-            PPhie0 (Expr);
+            PPhie1 (Expr);
             ConsumeRParen ();
             break;
 
@@ -263,6 +262,7 @@ void PPhie10 (PPExpr* Expr)
             NextToken ();
             PPhie10 (Expr);
             Expr->IVal = !Expr->IVal;
+            Expr->Flags &= ~PPEXPR_UNSIGNED;    /* Result is signed */
             break;
 
         case TOK_CEOF:
@@ -424,10 +424,10 @@ static void PPhie_compare (const token_t* Ops,    /* List of generators */
                 }
             }
         }
-    }
 
-    /* The result is signed */
-    Expr->Flags &= ~PPEXPR_UNSIGNED;
+        /* The result is signed */
+        Expr->Flags &= ~PPEXPR_UNSIGNED;
+    }
 }
 
 
@@ -711,7 +711,7 @@ static void PPhieQuest (PPExpr* Expr)
 
         /* Parse second expression */
         PPExprInit (&Expr2);
-        PPhie0 (&Expr2);
+        PPhie1 (&Expr2);
 
         /* Skip the colon */
         ConsumeColon ();
@@ -809,23 +809,6 @@ static void PPhie1 (PPExpr* Expr)
 
 
 
-static void PPhie0 (PPExpr* Expr)
-/* Handle the comma "," operator */
-{
-    PPhie1 (Expr);
-
-    while (CurTok.Tok == TOK_COMMA) {
-        /* Skip the comma */
-        NextToken ();
-        /* Reset the expression */
-        PPExprInit (Expr);
-        /* Use the next operand as the value instead */
-        PPhie1 (Expr);
-    }
-}
-
-
-
 void ParsePPExprInLine (PPExpr* Expr)
 /* Parse a line for PP expression */
 {
@@ -836,7 +819,7 @@ void ParsePPExprInLine (PPExpr* Expr)
 
     /* Parse */
     PPExprInit (Expr);
-    PPhie0 (Expr);
+    PPhie1 (Expr);
 
     /* If the evaluation fails, the result is always zero */
     if (PPEvaluationFailed) {
diff --git a/test/err/bug2523.c b/test/err/bug2523.c
new file mode 100644
index 000000000..7ab798557
--- /dev/null
+++ b/test/err/bug2523.c
@@ -0,0 +1,3 @@
+#if (1, 0) < 0
+#error
+#endif
diff --git a/test/val/bug2523.c b/test/val/bug2523.c
new file mode 100644
index 000000000..8db72d055
--- /dev/null
+++ b/test/val/bug2523.c
@@ -0,0 +1,29 @@
+#if (0u - 1) < 0
+#error
+#endif
+
+#if !1u - 1 > 0
+#error
+#endif
+
+#if (1 & 1u) - 2 < 0
+#error
+#endif
+
+#if (1 | 1u) - 2 < 0
+#error
+#endif
+
+#if (1 ^ 1u) - 2 < 0
+#error
+#endif
+
+#if (1u >> 1) - 2 < 0
+#error
+#endif
+
+#if (0u << 1) - 1 < 0
+#error
+#endif
+
+int main() { return 0; }