Index: tests/concurrency/waituntil/all_types.cfa
===================================================================
--- tests/concurrency/waituntil/all_types.cfa	(revision 71624f822be83d448dc75cfff5c0d96042467a34)
+++ tests/concurrency/waituntil/all_types.cfa	(revision 5329cba3bc0fd9973b02f354beaa0694fa72ca22)
@@ -39,5 +39,5 @@
         or when( i % 4 < 2 ) waituntil( B ) { consume_b_val( myTotal ); }
         or waituntil( c << C ) { if ( c == -1 ) break; myTotal += c; }
-        or when( i % 3 ) waituntil( timeout( 1`ms ) ) {}
+        or when( i % 3 ) waituntil( _timeout( 1`ms ) ) {}
         or when( i % 8 < 4 ) else {}
     }
@@ -53,5 +53,5 @@
         or waituntil( c << C ) { if ( c == -1 ) break; myTotal += c; }
         or waituntil( B ) { consume_b_val( myTotal ); }
-        or waituntil( timeout( 100`ns ) ) { }
+        or waituntil( _timeout( 100`ns ) ) { }
     }
     __atomic_fetch_add( &globalTotal, myTotal, __ATOMIC_SEQ_CST );
@@ -99,5 +99,5 @@
                 or when( j % 4 < 2 ) waituntil( B ) { produce_b_val( total ); }
                 and when( j % 8 < 4 ) waituntil( C << j ) { total += j; }
-                and waituntil( timeout( 1`ns ) ) {}
+                and waituntil( _timeout( 1`ns ) ) {}
                 if ( j == numtimes / 2 )
                     fulfil( F, val_to_deliver );
Index: tests/concurrency/waituntil/timeout.cfa
===================================================================
--- tests/concurrency/waituntil/timeout.cfa	(revision 71624f822be83d448dc75cfff5c0d96042467a34)
+++ tests/concurrency/waituntil/timeout.cfa	(revision 5329cba3bc0fd9973b02f354beaa0694fa72ca22)
@@ -6,14 +6,14 @@
 
 int main() {
-    waituntil( sleep( 1`ms ) ) { printf("timeout\n"); }
-    waituntil( timeout( 1`s ) ) { printf("timeout\n"); } or waituntil( timeout( 2`s ) ) { printf("timeout\n"); }
-    waituntil( timeout( 100`s ) ) { printf("timeout 1\n"); } or else { printf("else\n"); }
-    waituntil( timeout( 1`ns ) ) { printf("timeout\n"); } and waituntil( timeout( 2`s ) ) { printf("timeout\n"); }
+    waituntil( _timeout( 1`ms ) ) { printf("timeout\n"); }
+    waituntil( _timeout( 1`s ) ) { printf("timeout\n"); } or waituntil( _timeout( 2`s ) ) { printf("timeout\n"); }
+    waituntil( _timeout( 100`s ) ) { printf("timeout 1\n"); } or else { printf("else\n"); }
+    waituntil( _timeout( 1`ns ) ) { printf("timeout\n"); } and waituntil( _timeout( 2`s ) ) { printf("timeout\n"); }
     int count = 0;
     for ( i; 1000 )
-        waituntil( timeout( 1`ns ) ) { count++; } or else { count++; }
+        waituntil( _timeout( 1`ns ) ) { count++; } or else { count++; }
 
     assert( count == 1000 );
-    sleep( 1`ms );
+    _timeout( 1`ms );
     printf("done\n");
 }