always print backtrace when CTFE_BACKTRACE is set

No point in making the user also enable RUST_LOG

diff --git a/src/librustc/mir/interpret/error.rs b/src/librustc/mir/interpret/error.rs
index 4e44587a672ac61f714547c362571e5503191b5c..8e025f0d029b72f41237e1b1a5f6a6133c3fbd54 100644 (file)
--- a/src/librustc/mir/interpret/error.rs
+++ b/src/librustc/mir/interpret/error.rs
@@ -158,7 +158,7 @@ pub struct EvalError<'tcx> {
 impl<'tcx> EvalError<'tcx> {
     pub fn print_backtrace(&mut self) {
         if let Some(ref mut backtrace) = self.backtrace {
-            error!("{}", print_backtrace(&mut *backtrace));
+            eprintln!("{}", print_backtrace(&mut *backtrace));
         }
     }
 }
@@ -206,7 +206,7 @@ fn from(kind: EvalErrorKind<'tcx, u64>) -> Self {
 
                 if val == "immediate" {
                     // Print it now
-                    error!("{}", print_backtrace(&mut backtrace));
+                    eprintln!("{}", print_backtrace(&mut backtrace));
                     None
                 } else {
                     Some(Box::new(backtrace))