From 16d66b1933c6b562dc3aada375cc6d51c97a6e54 Mon Sep 17 00:00:00 2001
From: Avik Pal <avikpal@mit.edu>
Date: Sat, 5 Oct 2024 10:25:55 -0400
Subject: [PATCH 1/3] fix: don't use similar on prototype

---
 Project.toml             |  2 +-
 src/internal/jacobian.jl | 10 +++++-----
 2 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/Project.toml b/Project.toml
index d8ec44ac1..1651aab2a 100644
--- a/Project.toml
+++ b/Project.toml
@@ -1,7 +1,7 @@
 name = "NonlinearSolve"
 uuid = "8913a72c-1f9b-4ce2-8d82-65094dcecaec"
 authors = ["SciML"]
-version = "3.15.0"
+version = "3.15.1"
 
 [deps]
 ADTypes = "47edcb42-4c32-4615-8424-f2b9edc5f35b"
diff --git a/src/internal/jacobian.jl b/src/internal/jacobian.jl
index 390c0947f..0ab1286d1 100644
--- a/src/internal/jacobian.jl
+++ b/src/internal/jacobian.jl
@@ -92,13 +92,13 @@ function JacobianCache(prob, alg, f::F, fu_, u, p; stats, autodiff = nothing,
                 end
             end
         else
-            jac_proto = if eltype(f.jac_prototype) <: Bool
-                similar(f.jac_prototype, promote_type(eltype(fu), eltype(u)))
+            if eltype(f.jac_prototype) <: Bool
+                jac_proto = similar(f.jac_prototype, promote_type(eltype(fu), eltype(u)))
+                fill!(jac_proto, false)
+                jac_proto
             else
-                similar(f.jac_prototype)
+                f.jac_prototype
             end
-            fill!(jac_proto, false)
-            jac_proto
         end
     end
 

From b5981e2c8fed67b3071a787022aa277efb6be2d3 Mon Sep 17 00:00:00 2001
From: Avik Pal <avikpal@mit.edu>
Date: Sat, 5 Oct 2024 10:33:48 -0400
Subject: [PATCH 2/3] fix: use a copy

---
 src/internal/jacobian.jl | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/src/internal/jacobian.jl b/src/internal/jacobian.jl
index 0ab1286d1..0f885de47 100644
--- a/src/internal/jacobian.jl
+++ b/src/internal/jacobian.jl
@@ -92,12 +92,11 @@ function JacobianCache(prob, alg, f::F, fu_, u, p; stats, autodiff = nothing,
                 end
             end
         else
+            # NOTE: don't use similar because that might lead to an unwrapped array
             if eltype(f.jac_prototype) <: Bool
-                jac_proto = similar(f.jac_prototype, promote_type(eltype(fu), eltype(u)))
-                fill!(jac_proto, false)
-                jac_proto
+                promote_type(eltype(fu), eltype(u)).(f.jac_prototype)
             else
-                f.jac_prototype
+                copy(f.jac_prototype)
             end
         end
     end

From 834516a74acea89793562a7bf380d276a696cb48 Mon Sep 17 00:00:00 2001
From: Avik Pal <avikpal@mit.edu>
Date: Sat, 5 Oct 2024 14:05:52 -0400
Subject: [PATCH 3/3] fix: partial revert of previous fix

---
 src/internal/helpers.jl  | 5 ++---
 src/internal/jacobian.jl | 5 ++---
 2 files changed, 4 insertions(+), 6 deletions(-)

diff --git a/src/internal/helpers.jl b/src/internal/helpers.jl
index afc24ce5b..5334f11dc 100644
--- a/src/internal/helpers.jl
+++ b/src/internal/helpers.jl
@@ -1,9 +1,8 @@
 # Evaluate the residual function at a given point
 function evaluate_f(prob::AbstractNonlinearProblem{uType, iip}, u) where {uType, iip}
-    (; f, u0, p) = prob
+    (; f, p) = prob
     if iip
-        fu = f.resid_prototype === nothing ? zero(u) :
-             promote_type(eltype(u), eltype(f.resid_prototype)).(f.resid_prototype)
+        fu = f.resid_prototype === nothing ? zero(u) : similar(f.resid_prototype)
         f(fu, u, p)
     else
         fu = f(u, p)
diff --git a/src/internal/jacobian.jl b/src/internal/jacobian.jl
index 0f885de47..b78eb7383 100644
--- a/src/internal/jacobian.jl
+++ b/src/internal/jacobian.jl
@@ -92,11 +92,10 @@ function JacobianCache(prob, alg, f::F, fu_, u, p; stats, autodiff = nothing,
                 end
             end
         else
-            # NOTE: don't use similar because that might lead to an unwrapped array
             if eltype(f.jac_prototype) <: Bool
-                promote_type(eltype(fu), eltype(u)).(f.jac_prototype)
+                similar(f.jac_prototype, promote_type(eltype(fu), eltype(u)))
             else
-                copy(f.jac_prototype)
+                similar(f.jac_prototype)
             end
         end
     end