diff --git a/cue/testdata/builtins/validators.txtar b/cue/testdata/builtins/validators.txtar
index 1f2a59bfab1..468669bded9 100644
--- a/cue/testdata/builtins/validators.txtar
+++ b/cue/testdata/builtins/validators.txtar
@@ -114,18 +114,41 @@ issue2098: incomplete1: {
 	_a[0]
 }
 
+-- issue3418.cue --
+issue3418: t1: "foo" & matchN(1, [1&2]) & matchN(1, [_])
+issue3418: t2: "foo" & matchN(1, [_]) & matchN(1, [1&2])
+issue3418: t3: {
+	x: "foo"
+	x: matchN(1, [_])
+	x: matchN(1, [1&2])
+}
+issue3418: t4: {
+	x: "foo"
+	x: matchN(1, [1&2])
+	x: matchN(1, [_])
+}
+
 -- out/eval/stats --
-Leaks:  0
-Freed:  50
-Reused: 45
-Allocs: 5
-Retain: 0
+Leaks:  4
+Freed:  73
+Reused: 67
+Allocs: 10
+Retain: 8
 
-Unifications: 50
-Conjuncts:    91
-Disjuncts:    52
+Unifications: 77
+Conjuncts:    146
+Disjuncts:    83
 -- out/evalalpha --
 Errors:
+issue3418.0: conflicting values 2 and 1:
+    ./issue3418.cue:1:35
+    ./issue3418.cue:1:37
+issue3418.t3.0: conflicting values 2 and 1:
+    ./issue3418.cue:6:16
+    ./issue3418.cue:6:18
+issue3418.t4.0: conflicting values 2 and 1:
+    ./issue3418.cue:10:16
+    ./issue3418.cue:10:18
 callOfCallToValidator.e: cannot call previously called validator b:
     ./in.cue:94:5
 
@@ -224,12 +247,66 @@ Result:
       }
     }
   }
+  issue3418: (_|_){
+    // [eval]
+    t1: (_|_){
+      // [eval] issue3418.0: conflicting values 2 and 1:
+      //     ./issue3418.cue:1:35
+      //     ./issue3418.cue:1:37
+    }
+    t2: (_|_){
+      // [eval] issue3418.0: conflicting values 2 and 1:
+      //     ./issue3418.cue:2:52
+      //     ./issue3418.cue:2:54
+    }
+    t3: (_|_){
+      // [eval]
+      x: (_|_){
+        // [eval] issue3418.t3.0: conflicting values 2 and 1:
+        //     ./issue3418.cue:6:16
+        //     ./issue3418.cue:6:18
+      }
+    }
+    t4: (_|_){
+      // [eval]
+      x: (_|_){
+        // [eval] issue3418.t4.0: conflicting values 2 and 1:
+        //     ./issue3418.cue:10:16
+        //     ./issue3418.cue:10:18
+      }
+    }
+  }
 }
 -- diff/-out/evalalpha<==>+out/eval --
 diff old new
 --- old
 +++ new
-@@ -20,7 +20,6 @@
+@@ -1,15 +1,15 @@
+ Errors:
++issue3418.0: conflicting values 2 and 1:
++    ./issue3418.cue:1:35
++    ./issue3418.cue:1:37
++issue3418.t3.0: conflicting values 2 and 1:
++    ./issue3418.cue:6:16
++    ./issue3418.cue:6:18
++issue3418.t4.0: conflicting values 2 and 1:
++    ./issue3418.cue:10:16
++    ./issue3418.cue:10:18
+ callOfCallToValidator.e: cannot call previously called validator b:
+     ./in.cue:94:5
+-issue3418.t2: invalid value "foo" (does not satisfy matchN(1, _|_(issue3418.0: conflicting values 2 and 1))): 0 matched, expected 1:
+-    ./issue3418.cue:2:41
+-    ./issue3418.cue:2:16
+-    ./issue3418.cue:2:48
+-issue3418.t3.x: invalid value "foo" (does not satisfy matchN(1, _|_(issue3418.t3.0: conflicting values 2 and 1))): 0 matched, expected 1:
+-    ./issue3418.cue:6:5
+-    ./issue3418.cue:4:5
+-    ./issue3418.cue:5:5
+-    ./issue3418.cue:6:12
+ 
+ Result:
+ (_|_){
+@@ -29,7 +29,6 @@
        kv: (_|_){
          // [incomplete] incompleteError2.MyType.kv: invalid value {} (does not satisfy struct.MinFields(1)): len(fields) < MinFields(1) (0 < 1):
          //     ./in.cue:22:7
@@ -237,7 +314,7 @@ diff old new
          //     ./in.cue:22:24
        }
      }
-@@ -44,7 +43,6 @@
+@@ -53,7 +52,6 @@
        kv: (_|_){
          // [incomplete] violation.#MyType.kv: invalid value {} (does not satisfy struct.MinFields(1)): len(fields) < MinFields(1) (0 < 1):
          //     ./in.cue:49:7
@@ -245,7 +322,7 @@ diff old new
          //     ./in.cue:49:24
        }
      }
-@@ -91,15 +89,10 @@
+@@ -100,15 +98,10 @@
          0: (int){ 1 }
        }
      }
@@ -262,12 +339,67 @@ diff old new
          //     ./in.cue:112:20
        }
      }
+@@ -115,25 +108,31 @@
+   }
+   issue3418: (_|_){
+     // [eval]
+-    t1: (string){ "foo" }
++    t1: (_|_){
++      // [eval] issue3418.0: conflicting values 2 and 1:
++      //     ./issue3418.cue:1:35
++      //     ./issue3418.cue:1:37
++    }
+     t2: (_|_){
+-      // [eval] issue3418.t2: invalid value "foo" (does not satisfy matchN(1, _|_(issue3418.0: conflicting values 2 and 1))): 0 matched, expected 1:
+-      //     ./issue3418.cue:2:41
+-      //     ./issue3418.cue:2:16
+-      //     ./issue3418.cue:2:48
++      // [eval] issue3418.0: conflicting values 2 and 1:
++      //     ./issue3418.cue:2:52
++      //     ./issue3418.cue:2:54
+     }
+     t3: (_|_){
+       // [eval]
+       x: (_|_){
+-        // [eval] issue3418.t3.x: invalid value "foo" (does not satisfy matchN(1, _|_(issue3418.t3.0: conflicting values 2 and 1))): 0 matched, expected 1:
+-        //     ./issue3418.cue:6:5
+-        //     ./issue3418.cue:4:5
+-        //     ./issue3418.cue:5:5
+-        //     ./issue3418.cue:6:12
+-      }
+-    }
+-    t4: (struct){
+-      x: (string){ "foo" }
++        // [eval] issue3418.t3.0: conflicting values 2 and 1:
++        //     ./issue3418.cue:6:16
++        //     ./issue3418.cue:6:18
++      }
++    }
++    t4: (_|_){
++      // [eval]
++      x: (_|_){
++        // [eval] issue3418.t4.0: conflicting values 2 and 1:
++        //     ./issue3418.cue:10:16
++        //     ./issue3418.cue:10:18
++      }
+     }
+   }
+ }
 -- diff/todo/p2 --
 Missing error at incomplete1: index 0 is erased.
 -- out/eval --
 Errors:
 callOfCallToValidator.e: cannot call previously called validator b:
     ./in.cue:94:5
+issue3418.t2: invalid value "foo" (does not satisfy matchN(1, _|_(issue3418.0: conflicting values 2 and 1))): 0 matched, expected 1:
+    ./issue3418.cue:2:41
+    ./issue3418.cue:2:16
+    ./issue3418.cue:2:48
+issue3418.t3.x: invalid value "foo" (does not satisfy matchN(1, _|_(issue3418.t3.0: conflicting values 2 and 1))): 0 matched, expected 1:
+    ./issue3418.cue:6:5
+    ./issue3418.cue:4:5
+    ./issue3418.cue:5:5
+    ./issue3418.cue:6:12
 
 Result:
 (_|_){
@@ -371,6 +503,29 @@ Result:
       }
     }
   }
+  issue3418: (_|_){
+    // [eval]
+    t1: (string){ "foo" }
+    t2: (_|_){
+      // [eval] issue3418.t2: invalid value "foo" (does not satisfy matchN(1, _|_(issue3418.0: conflicting values 2 and 1))): 0 matched, expected 1:
+      //     ./issue3418.cue:2:41
+      //     ./issue3418.cue:2:16
+      //     ./issue3418.cue:2:48
+    }
+    t3: (_|_){
+      // [eval]
+      x: (_|_){
+        // [eval] issue3418.t3.x: invalid value "foo" (does not satisfy matchN(1, _|_(issue3418.t3.0: conflicting values 2 and 1))): 0 matched, expected 1:
+        //     ./issue3418.cue:6:5
+        //     ./issue3418.cue:4:5
+        //     ./issue3418.cue:5:5
+        //     ./issue3418.cue:6:12
+      }
+    }
+    t4: (struct){
+      x: (string){ "foo" }
+    }
+  }
 }
 -- out/compile --
 --- in.cue
@@ -478,3 +633,42 @@ Result:
     }
   }
 }
+--- issue3418.cue
+{
+  issue3418: {
+    t1: (("foo" & matchN(1, [
+      (1 & 2),
+    ])) & matchN(1, [
+      _,
+    ]))
+  }
+  issue3418: {
+    t2: (("foo" & matchN(1, [
+      _,
+    ])) & matchN(1, [
+      (1 & 2),
+    ]))
+  }
+  issue3418: {
+    t3: {
+      x: "foo"
+      x: matchN(1, [
+        _,
+      ])
+      x: matchN(1, [
+        (1 & 2),
+      ])
+    }
+  }
+  issue3418: {
+    t4: {
+      x: "foo"
+      x: matchN(1, [
+        (1 & 2),
+      ])
+      x: matchN(1, [
+        _,
+      ])
+    }
+  }
+}