\[\sqrt{x + 1} - \sqrt{x}\]
\sqrt{x + 1} - \sqrt{x}
double f(double x) {
        double r53327803 = x;
        double r53327804 = 1.0;
        double r53327805 = r53327803 + r53327804;
        double r53327806 = sqrt(r53327805);
        double r53327807 = sqrt(r53327803);
        double r53327808 = r53327806 - r53327807;
        return r53327808;
}

Reproduce

Please include this information when filing a bug report:

herbie shell --seed 1 
(FPCore (x)
  :name "sqrt(x+1)-sqrt(x)"
  (- (sqrt (+ x 1.0)) (sqrt x)))

Backtrace

flonum->ordinal: contract violation expected: Float given: 1.0f0 in: the 1st argument of (-> Float any) contract from: <pkgs>/math-lib/math/private/flonum/flonum-bits.rkt blaming: /var/www/herbie/src/interface.rkt (assuming the contract is correct) at: <pkgs>/math-lib/math/private/flonum/flonum-bits.rkt:9.9LC
raise-blame-error16/opt/racket-7.1/collects/racket/contract/private/blame.rkt3470
(unnamed)/opt/racket-7.1/collects/racket/contract/private/arrow-higher-order.rkt35733
ulp-difference/var/www/herbie/src/float.rkt460
(unnamed)/opt/racket-7.1/collects/racket/private/more-scheme.rkt26128
for-loop/var/www/herbie/src/points.rkt2252
errors/var/www/herbie/src/points.rkt2230
make-alt-table/var/www/herbie/src/core/alt-table.rkt330
(unnamed)/opt/racket-7.1/collects/racket/contract/private/arrow-val-first.rkt38818
setup-prog!34/var/www/herbie/src/mainloop.rkt670
run-improve43/var/www/herbie/src/mainloop.rkt3390
(unnamed)/opt/racket-7.1/collects/racket/private/more-scheme.rkt26128
(unnamed)/opt/racket-7.1/collects/racket/private/more-scheme.rkt26128