The following code has a bug... in 'mutate', 'gain_per_hour' uses 'hour' in the formula instead of 'hours'. Using 'hours' gives the right result.

library('dplyr')library('nycflights13')flights_sml =  flights %>%    select(year: day,           ends_with("delay"),           distance,           air_time)print(flights_sml)mu = flights_sml %>%  mutate(gain = arr_delay - dep_delay,              hours = air_time / 60,              gain_per_hour = gain / hour)print(mu)

and this is the stack trance:

RuntimeError:
java.lang.ArrayIndexOutOfBoundsException: -1 (RInternalError)
from com.oracle.truffle.r.nodes.function.FunctionDefinitionNode.execute(FunctionDefinitionNode.java:325)
from org.graalvm.compiler.truffle.runtime.OptimizedCallTarget.callProxy(OptimizedCallTarget.java:275)
from org.graalvm.compiler.truffle.runtime.OptimizedCallTarget.callRoot(OptimizedCallTarget.java:264)
from org.graalvm.compiler.truffle.runtime.OptimizedCallTarget.callBoundary(OptimizedCallTarget.java:251)
from org.graalvm.compiler.truffle.runtime.OptimizedCallTarget.doInvoke(OptimizedCallTarget.java:233)
from org.graalvm.compiler.truffle.runtime.OptimizedCallTarget.callDirect(OptimizedCallTarget.java:216)
from org.graalvm.compiler.truffle.runtime.OptimizedDirectCallNode.callProxy(OptimizedDirectCallNode.java:84)
from org.graalvm.compiler.truffle.runtime.OptimizedDirectCallNode.call(OptimizedDirectCallNode.java:68)
from com.oracle.truffle.r.nodes.function.call.CallRFunctionNode.execute(CallRFunctionNode.java:59)
from com.oracle.truffle.r.nodes.function.RCallNode$DispatchedCallNode.execute(RCallNode.java:1169)
Caused by:
-1 (ArrayIndexOutOfBoundsException)
from java.util.ArrayList.elementData(ArrayList.java:422)
from java.util.ArrayList.remove(ArrayList.java:499)
from com.oracle.truffle.r.ffi.impl.common.JavaUpCallsRFFIImpl.Rf_unprotect(JavaUpCallsRFFIImpl.java:1572)
from com.oracle.truffle.r.ffi.impl.upcalls.Rf_unprotectCall$Rf_unprotectCallFactory$1.execute(Rf_unprotectCall.java:54)
from org.graalvm.compiler.truffle.runtime.OptimizedCallTarget.callProxy(OptimizedCallTarget.java:275)
from org.graalvm.compiler.truffle.runtime.OptimizedCallTarget.callRoot(OptimizedCallTarget.java:264)
from org.graalvm.compiler.truffle.runtime.OptimizedCallTarget.callBoundary(OptimizedCallTarget.java:251)
from org.graalvm.compiler.truffle.runtime.OptimizedCallTarget.doInvoke(OptimizedCallTarget.java:233)
from org.graalvm.compiler.truffle.runtime.OptimizedCallTarget.callDirect(OptimizedCallTarget.java:216)
from org.graalvm.compiler.truffle.runtime.OptimizedDirectCallNode.callProxy(OptimizedDirectCallNode.java:84)