fix some issues discovered by JET

base/binaryplatforms.jl

@@ -873,7 +873,7 @@ function detect_libstdcxx_version(max_minor_version::Int=30)
     end
 
     # Brute-force our way through GLIBCXX_* symbols to discover which version we're linked against
-    hdl = Libdl.dlopen(first(libstdcxx_paths))
+    hdl = Libdl.dlopen(first(libstdcxx_paths))::Ptr{Cvoid}
     # Try all GLIBCXX versions down to GCC v4.8:
     # https://gcc.gnu.org/onlinedocs/libstdc++/manual/abi.html
     for minor_version in max_minor_version:-1:18

base/loading.jl

@@ -865,7 +865,11 @@ function explicit_manifest_uuid_path(project_file::String, pkg::PkgId)::Union{No
             uuid = get(entry, "uuid", nothing)::Union{Nothing, String}
             extensions = get(entry, "extensions", nothing)::Union{Nothing, Dict{String, Any}}
             if extensions !== nothing && haskey(extensions, pkg.name) && uuid !== nothing && uuid5(UUID(uuid), pkg.name) == pkg.uuid
-                p = normpath(dirname(locate_package(PkgId(UUID(uuid), name))), "..")
+                parent_path = locate_package(PkgId(UUID(uuid), name))
+                if parent_path === nothing
+                    error("failed to find source of parent package: \"$name\"")
+                end
+                p = normpath(dirname(parent_path), "..")
                 extfiledir = joinpath(p, "ext", pkg.name, pkg.name * ".jl")
                 isfile(extfiledir) && return extfiledir
                 return joinpath(p, "ext", pkg.name * ".jl")
@@ -1138,10 +1142,10 @@ function insert_extension_triggers(env::String, pkg::PkgId)::Union{Nothing,Missi
                         dep_name in weakdeps || continue
                         entries::Vector{Any}
                         if length(entries) != 1
-                            error("expected a single entry for $(repr(name)) in $(repr(project_file))")
+                            error("expected a single entry for $(repr(dep_name)) in $(repr(project_file))")
                         end
                         entry = first(entries)::Dict{String, Any}
-                        uuid = get(entry, "uuid", nothing)::Union{String, Nothing}
+                        uuid = entry["uuid"]::String
                         d_weakdeps[dep_name] = uuid
                     end
                     @assert length(d_weakdeps) == length(weakdeps)
@@ -1247,7 +1251,7 @@ function _tryrequire_from_serialized(modkey::PkgId, build_id::UInt128)
         loading = get(package_locks, modkey, false)
         if loading !== false
             # load already in progress for this module
-            loaded = wait(loading)
+            loaded = wait(loading::Threads.Condition)
         else
             package_locks[modkey] = Threads.Condition(require_lock)
             try
@@ -1282,7 +1286,7 @@ function _tryrequire_from_serialized(modkey::PkgId, path::String, ocachepath::Un
         loading = get(package_locks, modkey, false)
         if loading !== false
             # load already in progress for this module
-            loaded = wait(loading)
+            loaded = wait(loading::Threads.Condition)
         else
             for i in 1:length(depmods)
                 dep = depmods[i]
@@ -1324,7 +1328,7 @@ function _tryrequire_from_serialized(pkg::PkgId, path::String, ocachepath::Union
         pkgimage = !isempty(clone_targets)
         if pkgimage
             ocachepath !== nothing || return ArgumentError("Expected ocachepath to be provided")
-            isfile(ocachepath) || return ArgumentError("Ocachepath $ocachpath is not a file.")
+            isfile(ocachepath) || return ArgumentError("Ocachepath $ocachepath is not a file.")
             ocachepath == ocachefile_from_cachefile(path) || return ArgumentError("$ocachepath is not the expected ocachefile")
             # TODO: Check for valid clone_targets?
             isvalid_pkgimage_crc(io, ocachepath) || return ArgumentError("Invalid checksum in cache file $ocachepath.")
@@ -1404,13 +1408,13 @@ end
                 staledeps = true
                 break
             end
-            staledeps[i] = dep
+            (staledeps::Vector{Any})[i] = dep
         end
         if staledeps === true
             ocachefile = nothing
             continue
         end
-        restored = _include_from_serialized(pkg, path_to_try, ocachefile, staledeps)
+        restored = _include_from_serialized(pkg, path_to_try, ocachefile::String, staledeps::Vector{Any})
         if !isa(restored, Module)
             @debug "Deserialization checks failed while attempting to load cache from $path_to_try" exception=restored
         else
@@ -1667,7 +1671,7 @@ function _require(pkg::PkgId, env=nothing)
     loading = get(package_locks, pkg, false)
     if loading !== false
         # load already in progress for this module
-        return wait(loading)
+        return wait(loading::Threads.Condition)
     end
     package_locks[pkg] = Threads.Condition(require_lock)
 
@@ -2160,12 +2164,12 @@ function compilecache(pkg::PkgId, path::String, internal_stderr::IO = stderr, in
                     rename(tmppath_so, ocachefile::String; force=true)
                 catch e
                     e isa IOError || rethrow()
-                    isfile(ocachefile) || rethrow()
+                    isfile(ocachefile::String) || rethrow()
                     # Windows prevents renaming a file that is in use so if there is a Julia session started
                     # with a package image loaded, we cannot rename that file.
                     # The code belows append a `_i` to the name of the cache file where `i` is the smallest number such that
                     # that cache file does not exist.
-                    ocachename, ocacheext = splitext(ocachefile)
+                    ocachename, ocacheext = splitext(ocachefile::String)
                     old_cachefiles = Set(readdir(cachepath))
                     num = 1
                     while true
@@ -2185,7 +2189,7 @@ function compilecache(pkg::PkgId, path::String, internal_stderr::IO = stderr, in
     finally
         rm(tmppath, force=true)
         if cache_objects
-            rm(tmppath_o, force=true)
+            rm(tmppath_o::String, force=true)
             rm(tmppath_so, force=true)
         end
     end

stdlib/Artifacts/src/Artifacts.jl

@@ -52,7 +52,7 @@ function artifacts_dirs(args...)
         return String[abspath(depot, "artifacts", args...) for depot in Base.DEPOT_PATH]
     else
         # If we've been given an override, use _only_ that directory.
-        return String[abspath(ARTIFACTS_DIR_OVERRIDE[], args...)]
+        return String[abspath(ARTIFACTS_DIR_OVERRIDE[]::String, args...)]
     end
 end
 

stdlib/FileWatching/src/FileWatching.jl

@@ -215,7 +215,7 @@ mutable struct _FDWatcher
                 t.refcount = (0, 0)
                 t.active = (false, false)
                 @static if Sys.isunix()
-                    if FDWatchers[t.fdnum] == t
+                    if FDWatchers[t.fdnum] === t
                         FDWatchers[t.fdnum] = nothing
                     end
                 end

stdlib/LibGit2/src/LibGit2.jl

@@ -848,7 +848,7 @@ function rebase!(repo::GitRepo, upstream::AbstractString="", newbase::AbstractSt
             end
         finally
             if !isempty(newbase)
-                close(onto_ann)
+                close(onto_ann::GitAnnotated)
             end
             close(upst_ann)
             close(head_ann)

stdlib/LibGit2/src/callbacks.jl

@@ -276,18 +276,20 @@ function credentials_callback(libgit2credptr::Ptr{Ptr{Cvoid}}, url_ptr::Cstring,
     # information cached inside the payload.
     if isempty(p.url)
         p.url = unsafe_string(url_ptr)
-        m = match(URL_REGEX, p.url)
+        m = match(URL_REGEX, p.url)::RegexMatch
 
         p.scheme = something(m[:scheme], SubString(""))
         p.username = something(m[:user], SubString(""))
-        p.host = m[:host]
+        p.host = something(m[:host])
 
         # When an explicit credential is supplied we will make sure to use the given
         # credential during the first callback by modifying the allowed types. The
         # modification only is in effect for the first callback since `allowed_types` cannot
         # be mutated.
-        if p.explicit !== nothing
-            cred = p.explicit
+        cache = p.cache
+        explicit = p.explicit
+        if explicit !== nothing
+            cred = explicit
 
             # Copy explicit credentials to avoid mutating approved credentials.
             # invalidation fix from cred being non-inferrable
@@ -300,16 +302,15 @@ function credentials_callback(libgit2credptr::Ptr{Ptr{Cvoid}}, url_ptr::Cstring,
             else
                 allowed_types &= Cuint(0)  # Unhandled credential type
             end
-        elseif p.cache !== nothing
+        elseif cache !== nothing
             cred_id = credential_identifier(p.scheme, p.host)
 
             # Perform a deepcopy as we do not want to mutate approved cached credentials
-            if haskey(p.cache, cred_id)
-                # invalidation fix from p.cache[cred_id] being non-inferrable
-                p.credential = Base.invokelatest(deepcopy, p.cache[cred_id])
+            if haskey(cache, cred_id)
+                # invalidation fix from cache[cred_id] being non-inferrable
+                p.credential = Base.invokelatest(deepcopy, cache[cred_id])
             end
         end
-
         p.first_pass = true
     else
         p.first_pass = false
@@ -447,7 +448,7 @@ function ssh_knownhost_check(
 )
     if (m = match(r"^(.+):(\d+)$", host)) !== nothing
         host = m.captures[1]
-        port = parse(Int, m.captures[2])
+        port = parse(Int, something(m.captures[2]))
     else
         port = 22 # default SSH port
     end

stdlib/LibGit2/src/gitcredential.jl

@@ -46,7 +46,8 @@ function Base.shred!(cred::GitCredential)
     cred.host = nothing
     cred.path = nothing
     cred.username = nothing
-    cred.password !== nothing && Base.shred!(cred.password)
+    pwd = cred.password
+    pwd !== nothing && Base.shred!(pwd)
     cred.password = nothing
     return cred
 end
@@ -122,7 +123,7 @@ function Base.read!(io::IO, cred::GitCredential)
         if key == "url"
             # Any components which are missing from the URL will be set to empty
             # https://git-scm.com/docs/git-credential#git-credential-codeurlcode
-            Base.shred!(parse(GitCredential, value)) do urlcred
+            Base.shred!(parse(GitCredential, value::AbstractString)) do urlcred
                 copy!(cred, urlcred)
             end
         elseif key in GIT_CRED_ATTRIBUTES

stdlib/LibGit2/src/types.jl

@@ -1389,7 +1389,8 @@ CredentialPayload(p::CredentialPayload) = p
 function Base.shred!(p::CredentialPayload)
     # Note: Avoid shredding the `explicit` or `cache` fields as these are just references
     # and it is not our responsibility to shred them.
-    p.credential !== nothing && Base.shred!(p.credential)
+    credential = p.credential
+    credential !== nothing && Base.shred!(credential)
     p.credential = nothing
 end
 
@@ -1430,8 +1431,9 @@ function approve(p::CredentialPayload; shred::Bool=true)
 
     # Each `approve` call needs to avoid shredding the passed in credential as we need
     # the credential information intact for subsequent approve calls.
-    if p.cache !== nothing
-        approve(p.cache, cred, p.url)
+    cache = p.cache
+    if cache !== nothing
+        approve(cache, cred, p.url)
         shred = false  # Avoid wiping `cred` as this would also wipe the cached copy
     end
     if p.allow_git_helpers
@@ -1460,8 +1462,9 @@ function reject(p::CredentialPayload; shred::Bool=true)
 
     # Note: each `reject` call needs to avoid shredding the passed in credential as we need
     # the credential information intact for subsequent reject calls.
-    if p.cache !== nothing
-        reject(p.cache, cred, p.url)
+    cache = p.cache
+    if cache !== nothing
+        reject(cache, cred, p.url)
     end
     if p.allow_git_helpers
         reject(p.config, cred, p.url)

stdlib/LibGit2/src/utils.jl

@@ -171,7 +171,7 @@ end
 
 function credential_identifier(url::AbstractString)
     m = match(URL_REGEX, url)
-    scheme = something(m[:scheme], "")
-    host = m[:host]
+    scheme = something(m[:scheme], SubString(""))
+    host = something(m[:host])
     credential_identifier(scheme, host)
 end