Added a warning if the result of a compare operation is constant. This should

protect against missing parenthesis like in (si & 0x7F == 0). Hopefully
without too many false positives.

git-svn-id: svn://svn.cc65.org/cc65/trunk@4057 b7a2c559-68d2-44c3-8de9-860c34a00d81

diff --git a/src/cc65/expr.c b/src/cc65/expr.c
index 01436b96f2d6e20a0d9fa1e1341ae49e694785b9..e8c962967b0084c2122985ad8865db006fe2657e 100644 (file)
--- a/src/cc65/expr.c
+++ b/src/cc65/expr.c
@@ -1864,17 +1864,17 @@ static void hie_compare (const GenDesc* Ops,    /* List of generators */
        /* Make sure, the types are compatible */
        if (IsClassInt (Expr->Type)) {
            if (!IsClassInt (Expr2.Type) && !(IsClassPtr(Expr2.Type) && ED_IsNullPtr(Expr))) {
-               Error ("Incompatible types");
+               Error ("Incompatible types");
            }
        } else if (IsClassPtr (Expr->Type)) {
            if (IsClassPtr (Expr2.Type)) {
-               /* Both pointers are allowed in comparison if they point to
-                * the same type, or if one of them is a void pointer.
+               /* Both pointers are allowed in comparison if they point to
+                * the same type, or if one of them is a void pointer.
                 */
                        Type* left  = Indirect (Expr->Type);
-               Type* right = Indirect (Expr2.Type);
-               if (TypeCmp (left, right) < TC_EQUAL && left->C != T_VOID && right->C != T_VOID) {
-                   /* Incomatible pointers */
+               Type* right = Indirect (Expr2.Type);
+               if (TypeCmp (left, right) < TC_EQUAL && left->C != T_VOID && right->C != T_VOID) {
+                   /* Incomatible pointers */
                    Error ("Incompatible types");
                }
            } else if (!ED_IsNullPtr (&Expr2)) {
@@ -1885,6 +1885,8 @@ static void hie_compare (const GenDesc* Ops,    /* List of generators */
        /* Check for const operands */
        if (ED_IsConstAbs (Expr) && rconst) {
 
+            Warning ("Result of comparison is constant");
+
                    /* Both operands are constant, remove the generated code */
                    RemoveCode (&Mark1);
 
@@ -2940,7 +2942,7 @@ static void addsubeq (const GenDesc* Gen, ExprDesc *Expr)
                    g_scale (TypeOf (Expr2.Type), CheckedSizeOf (Indirect (Expr->Type)));
        }
     }
-            
+
     /* Setup the code generator flags */
     lflags |= TypeOf (Expr->Type) | GlobalModeFlags (Expr) | CF_FORCECHAR;
     rflags |= TypeOf (Expr2.Type) | CF_FORCECHAR;
@@ -2950,7 +2952,7 @@ static void addsubeq (const GenDesc* Gen, ExprDesc *Expr)
 
     /* Output apropriate code depending on the location */
     switch (ED_GetLoc (Expr)) {
-                                                                         
+
         case E_LOC_ABS:
             /* Absolute: numeric address or const */
             if (Gen->Tok == TOK_PLUS_ASSIGN) {