\[0.0 \lt a \lt b + c \land 0.0 \lt b \lt a + c \land 0.0 \lt c \lt a + b\]

\[\sqrt{\left(\left(\frac{\left(a + b\right) + c}{2} \cdot \left(\frac{\left(a + b\right) + c}{2} - a\right)\right) \cdot \left(\frac{\left(a + b\right) + c}{2} - b\right)\right) \cdot \left(\frac{\left(a + b\right) + c}{2} - c\right)}\]

\sqrt{\left(\left(\frac{\left(a + b\right) + c}{2} \cdot \left(\frac{\left(a + b\right) + c}{2} - a\right)\right) \cdot \left(\frac{\left(a + b\right) + c}{2} - b\right)\right) \cdot \left(\frac{\left(a + b\right) + c}{2} - c\right)}

double code(double a, double b, double c) {
	return ((double) sqrt(((double) (((double) (((double) (((double) (((double) (((double) (a + b)) + c)) / 2.0)) * ((double) (((double) (((double) (((double) (a + b)) + c)) / 2.0)) - a)))) * ((double) (((double) (((double) (((double) (a + b)) + c)) / 2.0)) - b)))) * ((double) (((double) (((double) (((double) (a + b)) + c)) / 2.0)) - c))))));
}

Reproduce

Please include this information when filing a bug report:

herbie shell --seed 2020165 
(FPCore (a b c)
  :name "Area of a triangle"
  :precision binary64
  :pre (and (< 0.0 a (+ b c)) (< 0.0 b (+ a c)) (< 0.0 c (+ a b)))

  :herbie-target
  (/ (sqrt (* (* (* (+ a (+ b c)) (- c (- a b))) (+ c (- a b))) (+ a (- b c)))) 4.0)

  (sqrt (* (* (* (/ (+ (+ a b) c) 2.0) (- (/ (+ (+ a b) c) 2.0) a)) (- (/ (+ (+ a b) c) 2.0) b)) (- (/ (+ (+ a b) c) 2.0) c))))

Backtrace

ival-hi: contract violation expected: ival? given: #<procedure:interval>		L	C
for-loop	/data/pavpan/nightlies/herbie/ival-find-range/src/sampling.rkt	37	11
hyperrect-weight	/data/pavpan/nightlies/herbie/ival-find-range/src/sampling.rkt	36	0
total-weight	/data/pavpan/nightlies/herbie/ival-find-range/src/sampling.rkt	113	2
log-space-improvement	/data/pavpan/nightlies/herbie/ival-find-range/src/sampling.rkt	110	0
(unnamed)	/opt/racket-7.5/collects/racket/contract/private/arrow-higher-order.rkt	375	33
get-hyperrects	/data/pavpan/nightlies/herbie/ival-find-range/src/sampling.rkt	123	0
make-sampler	/data/pavpan/nightlies/herbie/ival-find-range/src/sampling.rkt	147	0
prepare-points-intervals	/data/pavpan/nightlies/herbie/ival-find-range/src/points.rkt	90	0
run-improve47	/data/pavpan/nightlies/herbie/ival-find-range/src/mainloop.rkt	365	0
.../more-scheme.rkt:261:28	unknown
run	/opt/racket-7.5/share/pkgs/profile-lib/main.rkt	39	2
profile-thunk16	/opt/racket-7.5/share/pkgs/profile-lib/main.rkt	9	0
(unnamed)	/opt/racket-7.5/collects/racket/private/more-scheme.rkt	261	28

Reproduce

herbie shell --seed 2020165 
(FPCore (a b c)
  :name "Area of a triangle"
  :precision binary64
  :pre (and (< 0.0 a (+ b c)) (< 0.0 b (+ a c)) (< 0.0 c (+ a b)))

  :herbie-target
  (/ (sqrt (* (* (* (+ a (+ b c)) (- c (- a b))) (+ c (- a b))) (+ a (- b c)))) 4.0)

  (sqrt (* (* (* (/ (+ (+ a b) c) 2.0) (- (/ (+ (+ a b) c) 2.0) a)) (- (/ (+ (+ a b) c) 2.0) b)) (- (/ (+ (+ a b) c) 2.0) c))))