((eval '(lambda () (- (/ 1. (expt 2 55)) 1)) (scheme-report-environment 5))) ((eval '(lambda () (- (/ (expt 2 55)) 1)) (scheme-report-environment 5))) Does not fail: (eval `(- (* 70147833903540842 (/ 1. (expt 2 55))) 1) (scheme-report-environment 5))