kernel: reject invalid AND-filters

src/c_oper1.c

@@ -890,17 +890,20 @@ static Obj  HdlrFunc3 (
       t_4 = (EQ( t_5, t_6 ) ? True : False);
       t_3 = t_4;
      }
-     else {
-      CHECK_FUNC( l_match )
+     else if (IS_FILTER( l_match ) ) {
       C_SUM_FIA( t_8, l_k, l_j )
       C_SUM_FIA( t_7, t_8, INTOBJ_INT(1) )
       CHECK_INT_POS( t_7 )
       C_ELM_LIST_FPL( t_6, l_methods, t_7 )
       C_ELM_LIST_FPL( t_7, a_flags, l_j )
       t_5 = (EQ( t_6, t_7 ) ? True : False);
-      CHECK_FUNC( t_5 )
       t_3 = NewAndFilter( l_match, t_5 );
      }
+     else {
+      ErrorQuit(
+      "<expr> must be 'true' or 'false' or a filter (not a %s)",
+      (Int)TNAM_OBJ(l_match), 0L );
+     }
      l_match = t_3;
 
     }
@@ -2667,14 +2670,17 @@ static Obj  HdlrFunc7 (
      CHECK_BOOL( t_6 )
      t_5 = t_6;
     }
-    else {
-     CHECK_FUNC( l_cats )
+    else if (IS_FILTER( l_cats ) ) {
      t_8 = GC_FILTERS;
      CHECK_BOUND( t_8, "FILTERS" )
      C_ELM_LIST_FPL( t_7, t_8, l_i )
-     CHECK_FUNC( t_7 )
      t_5 = NewAndFilter( l_cats, t_7 );
     }
+    else {
+     ErrorQuit(
+     "<expr> must be 'true' or 'false' or a filter (not a %s)",
+     (Int)TNAM_OBJ(l_cats), 0L );
+    }
     l_cats = t_5;
 
     /* rank := rank - RankFilter( FILTERS[i] ); */
@@ -3201,13 +3207,16 @@ static Obj  HdlrFunc15 (
   t_3 = (EQ( t_4, a_key ) ? True : False);
   t_1 = t_3;
  }
- else {
-  CHECK_FUNC( t_2 )
+ else if (IS_FILTER( t_2 ) ) {
   C_ELM_LIST_FPL( t_5, l_known, l_i )
   t_4 = (EQ( t_5, a_key ) ? True : False);
-  CHECK_FUNC( t_4 )
   t_1 = NewAndFilter( t_2, t_4 );
  }
+ else {
+  ErrorQuit(
+  "<expr> must be 'true' or 'false' or a filter (not a %s)",
+  (Int)TNAM_OBJ(t_2), 0L );
+ }
  RES_BRK_CURR_STAT();
  SWITCH_TO_OLD_FRAME(oldFrame);
  return t_1;

src/c_type1.c

@@ -237,11 +237,14 @@ static Obj  HdlrFunc2 (
   CHECK_BOOL( a_tester )
   t_5 = a_tester;
  }
- else {
-  CHECK_FUNC( t_6 )
-  CHECK_FUNC( a_tester )
+ else if (IS_FILTER( t_6 ) ) {
   t_5 = NewAndFilter( t_6, a_tester );
  }
+ else {
+  ErrorQuit(
+  "<expr> must be 'true' or 'false' or a filter (not a %s)",
+  (Int)TNAM_OBJ(t_6), 0L );
+ }
  SET_ELM_PLIST( t_4, 1, t_5 );
  CHANGED_BAG( t_4 );
  t_5 = GC_GETTER__FLAGS;

src/compiler.c

@@ -1312,13 +1312,18 @@ CVar CompAnd (
     Emit( "}\n" );
 
     /* emit the code for the case that the left value is a filter          */
-    Emit( "else {\n" );
-    CompCheckFunc( left );
+    Emit( "else if (IS_FILTER( %c ) ) {\n", left );
     right2 = CompExpr(READ_EXPR(expr, 1));
-    CompCheckFunc( right2 );
     Emit( "%c = NewAndFilter( %c, %c );\n", val, left, right2 );
     Emit( "}\n" );
 
+    /* signal an error                                                     */
+    Emit( "else {\n" );
+    Emit( "ErrorQuit(\n"
+            "\"<expr> must be 'true' or 'false' or a filter (not a %%s)\",\n"
+            "(Int)TNAM_OBJ(%c), 0L );\n", left );
+    Emit( "}\n" );
+
     /* we know precious little about the result                            */
     MergeInfoCVars( INFO_FEXP(CURR_FUNC()), only_left );
     SetInfoCVar( val, W_BOUND );

src/exprs.c

@@ -183,23 +183,16 @@ Obj             EvalAnd (
     }
 
     /* handle the 'and' of two filters                                    */
-    else if ( TNUM_OBJ(opL) == T_FUNCTION ) {
+    else if (IS_FILTER(opL)) {
         tmp = READ_EXPR(expr, 1);
         opR = EVAL_EXPR( tmp );
-        if ( TNUM_OBJ(opR) == T_FUNCTION ) {
-            return NewAndFilter( opL, opR );
-        }
-        else {
-            ErrorQuit(
-                "<expr> must be 'true' or 'false' (not a %s)",
-                (Int)TNAM_OBJ(opL), 0L );
-        }
+        return NewAndFilter(opL, opR);
     }
 
     /* signal an error                                                     */
     else {
         ErrorQuit(
-            "<expr> must be 'true' or 'false' (not a %s)",
+            "<expr> must be 'true' or 'false' or a filter (not a %s)",
             (Int)TNAM_OBJ(opL), 0L );
     }
 

src/hpc/c_oper1.c

@@ -922,17 +922,20 @@ static Obj  HdlrFunc3 (
       t_4 = (EQ( t_5, t_6 ) ? True : False);
       t_3 = t_4;
      }
-     else {
-      CHECK_FUNC( l_match )
+     else if (IS_FILTER( l_match ) ) {
       C_SUM_FIA( t_8, l_k, l_j )
       C_SUM_FIA( t_7, t_8, INTOBJ_INT(1) )
       CHECK_INT_POS( t_7 )
       C_ELM_LIST_FPL( t_6, l_methods, t_7 )
       C_ELM_LIST_FPL( t_7, a_flags, l_j )
       t_5 = (EQ( t_6, t_7 ) ? True : False);
-      CHECK_FUNC( t_5 )
       t_3 = NewAndFilter( l_match, t_5 );
      }
+     else {
+      ErrorQuit(
+      "<expr> must be 'true' or 'false' or a filter (not a %s)",
+      (Int)TNAM_OBJ(l_match), 0L );
+     }
      l_match = t_3;
 
     }
@@ -2726,14 +2729,17 @@ static Obj  HdlrFunc7 (
      CHECK_BOOL( t_6 )
      t_5 = t_6;
     }
-    else {
-     CHECK_FUNC( l_cats )
+    else if (IS_FILTER( l_cats ) ) {
      t_8 = GC_FILTERS;
      CHECK_BOUND( t_8, "FILTERS" )
      C_ELM_LIST_FPL( t_7, t_8, l_i )
-     CHECK_FUNC( t_7 )
      t_5 = NewAndFilter( l_cats, t_7 );
     }
+    else {
+     ErrorQuit(
+     "<expr> must be 'true' or 'false' or a filter (not a %s)",
+     (Int)TNAM_OBJ(l_cats), 0L );
+    }
     l_cats = t_5;
 
     /* rank := rank - RankFilter( FILTERS[i] ); */
@@ -3264,13 +3270,16 @@ static Obj  HdlrFunc15 (
   t_3 = (EQ( t_4, a_key ) ? True : False);
   t_1 = t_3;
  }
- else {
-  CHECK_FUNC( t_2 )
+ else if (IS_FILTER( t_2 ) ) {
   C_ELM_LIST_FPL( t_5, l_known, l_i )
   t_4 = (EQ( t_5, a_key ) ? True : False);
-  CHECK_FUNC( t_4 )
   t_1 = NewAndFilter( t_2, t_4 );
  }
+ else {
+  ErrorQuit(
+  "<expr> must be 'true' or 'false' or a filter (not a %s)",
+  (Int)TNAM_OBJ(t_2), 0L );
+ }
  RES_BRK_CURR_STAT();
  SWITCH_TO_OLD_FRAME(oldFrame);
  return t_1;

src/hpc/c_type1.c

@@ -276,11 +276,14 @@ static Obj  HdlrFunc2 (
   CHECK_BOOL( a_tester )
   t_5 = a_tester;
  }
- else {
-  CHECK_FUNC( t_6 )
-  CHECK_FUNC( a_tester )
+ else if (IS_FILTER( t_6 ) ) {
   t_5 = NewAndFilter( t_6, a_tester );
  }
+ else {
+  ErrorQuit(
+  "<expr> must be 'true' or 'false' or a filter (not a %s)",
+  (Int)TNAM_OBJ(t_6), 0L );
+ }
  SET_ELM_PLIST( t_4, 1, t_5 );
  CHANGED_BAG( t_4 );
  t_5 = GC_GETTER__FLAGS;

src/intrprtr.c

@@ -1369,21 +1369,14 @@ void            IntrAnd ( void )
     }
 
     /* handle the 'and' of two filters                                    */
-    else if ( IS_OPERATION(opL) ) {
-        if ( IS_OPERATION(opR) ) {
-            PushObj( NewAndFilter( opL, opR ) );
-        }
-        else {
-            ErrorQuit(
-                "<expr> must be 'true' or 'false' (not a %s)",
-                (Int)TNAM_OBJ(opL), 0L );
-        }
+    else if (IS_FILTER(opL)) {
+        PushObj(NewAndFilter(opL, opR));
     }
 
     /* signal an error                                                     */
     else {
         ErrorQuit(
-            "<expr> must be 'true' or 'false' (not a %s)",
+            "<expr> must be 'true' or 'false' or a filter (not a %s)",
             (Int)TNAM_OBJ(opL), 0L );
     }
 }

src/opers.c

@@ -1248,6 +1248,14 @@ Obj NewAndFilter (
     Obj                 str;
     char*               s;
 
+    if (!IS_FILTER(oper1))
+        ErrorQuit("<oper1> must be a filter (not a %s)", (Int)TNAM_OBJ(oper1),
+                  0);
+
+    if (!IS_FILTER(oper2))
+        ErrorQuit("<oper2> must be a filter (not a %s)", (Int)TNAM_OBJ(oper2),
+                  0);
+
     if ( oper1 == ReturnTrueFilter )
         return oper2;
 

src/opers.h

@@ -247,6 +247,7 @@ static inline Int IS_FILTER(Obj oper)
     return v & OPER_IS_FILTER;
 }
 
+
 /****************************************************************************
 **
 *F  SET_IS_FILTER( <oper> ) . . . . . . . . . . .  mark operation as a filter

tst/test-compile/and_filter.g

@@ -0,0 +1,18 @@
+runtest := function()
+
+Print(false and 1, "\n");
+Print(true or 1, "\n");
+Print(function() return false and 1; end(), "\n");
+Print(function() return true or 1; end(), "\n");
+Print(IsAssociative and IsAssociative, "\n");
+
+# ensure we don't abort after an error
+BreakOnError := false;
+
+# trigger error 1:
+CALL_WITH_CATCH({} -> Center and IsAssociative, []);
+
+# trigger error 2:
+CALL_WITH_CATCH({} -> IsAssociative and Center, []);
+
+end;