Add a test for profile deserialization (#21575)

xref #21025 which is fixed on master, and a one-character fix on release-0.5,
but should be tested on both branches
(cherry picked from commit 4ddd9fa)

change Int64 to UInt64 in deserialize method,
and UInt64 to UInt in test, for release-0.5

Author: tkelman

base/stacktraces.jl

@@ -37,7 +37,7 @@ Stack information representing execution context, with the following fields:
 
   True if the code is from an inlined frame.
 
-- `pointer::Int64`
+- `pointer::UInt64`
 
   Representation of the pointer to the execution context as returned by `backtrace`.
 
@@ -109,7 +109,7 @@ function deserialize(s::AbstractSerializer, ::Type{StackFrame})
     line = read(s.io, Int)
     from_c = read(s.io, Bool)
     inlined = read(s.io, Bool)
-    pointer = read(s.io, Int64)
+    pointer = read(s.io, UInt64)
     return StackFrame(func, file, line, Nullable{LambdaInfo}(), from_c, inlined, pointer)
 end
 

test/profile.jl

@@ -11,6 +11,17 @@ end
 
 Profile.clear()
 @profile busywait(1, 20)
+
+let r = Profile.retrieve()
+    mktemp() do path, io
+        serialize(io, r)
+        close(io)
+        open(path) do io
+            @test isa(deserialize(io), Tuple{Vector{UInt},Dict{UInt,Vector{StackFrame}}})
+        end
+    end
+end
+
 let iobuf = IOBuffer()
     Profile.print(iobuf, format=:tree, C=true)
     str = takebuf_string(iobuf)