Precompile trust region only on v1.7+

Fixes #121

Author: ChrisRackauckas

src/NonlinearSolve.jl

@@ -38,13 +38,21 @@ import SnoopPrecompile
 
 SnoopPrecompile.@precompile_all_calls begin for T in (Float32, Float64)
     prob = NonlinearProblem{false}((u, p) -> u .* u .- p, T(0.1), T(2))
-    for alg in (NewtonRaphson,)
-        solve(prob, alg(), abstol = T(1e-2))
+
+    precompile_algs = if VERSION >= v"1.7"
+        (NewtonRaphson(), TrustRegion())
+    else
+        (NewtonRaphson(),)
+    end
+
+    
+    for alg in precompile_algs
+        solve(prob, alg, abstol = T(1e-2))
     end
 
     prob = NonlinearProblem{true}((du, u, p) -> du[1] = u[1] * u[1] - p[1], T[0.1], T[2])
-    for alg in (NewtonRaphson,)
-        solve(prob, alg(), abstol = T(1e-2))
+    for alg in precompile_algs
+        solve(prob, alg, abstol = T(1e-2))
     end
 end end