closes #18433 (#18484)

* beneficial refactoring; use system.Endianness

* closes #18433

compiler/options.nim

@@ -592,8 +592,8 @@ proc isDefined*(conf: ConfigRef; symbol: string): bool =
       result = conf.target.targetOS == osNintendoSwitch
     of "freertos", "lwip":
       result = conf.target.targetOS == osFreeRTOS
-    of "littleendian": result = CPU[conf.target.targetCPU].endian == platform.littleEndian
+    of "littleendian": result = CPU[conf.target.targetCPU].endian == littleEndian
-    of "bigendian": result = CPU[conf.target.targetCPU].endian == platform.bigEndian
+    of "bigendian": result = CPU[conf.target.targetCPU].endian == bigEndian
     of "cpu8": result = CPU[conf.target.targetCPU].bit == 8
     of "cpu16": result = CPU[conf.target.targetCPU].bit == 16
     of "cpu32": result = CPU[conf.target.targetCPU].bit == 32

compiler/platform.nim

@@ -196,13 +196,11 @@ type
     cpuSparc64, cpuMips64, cpuMips64el, cpuRiscV32, cpuRiscV64, cpuEsp, cpuWasm32
 
 type
-  TEndian* = enum
+  TInfoCPU* = tuple[name: string, intSize: int, endian: Endianness,
-    littleEndian, bigEndian
-  TInfoCPU* = tuple[name: string, intSize: int, endian: TEndian,
                     floatSize, bit: int]
 
 const
-  EndianToStr*: array[TEndian, string] = ["littleEndian", "bigEndian"]
+  EndianToStr*: array[Endianness, string] = ["littleEndian", "bigEndian"]
   CPU*: array[succ(low(TSystemCPU))..high(TSystemCPU), TInfoCPU] = [
     (name: "i386", intSize: 32, endian: littleEndian, floatSize: 64, bit: 32),
     (name: "m68k", intSize: 32, endian: bigEndian, floatSize: 64, bit: 32),

tests/arc/tfuncobj.nim

@@ -0,0 +1,38 @@
+discard """
+  outputsub: '''f1
+f2
+f3'''
+  cmd: "nim c --gc:orc $file"
+  valgrind: true
+"""
+
+type
+  FuncObj = object
+    fn: proc (env: pointer) {.cdecl.}
+    env: pointer
+
+proc `=destroy`(x: var FuncObj) =
+  GC_unref(cast[RootRef](x.env))
+
+proc `=copy`(x: var FuncObj, y: FuncObj) {.error.}
+
+# bug #18433
+
+proc main =
+  var fs: seq[FuncObj]
+
+  proc wrap(p: proc()) =
+    proc closeOver() = p()
+    let env = rawEnv closeOver
+    GC_ref(cast[RootRef](env))
+    fs.add(FuncObj(fn: cast[proc(env: pointer){.cdecl.}](rawProc closeOver), env: env))
+
+  wrap(proc() {.closure.} = echo "f1")
+  wrap(proc() {.closure.} = echo "f2")
+  wrap(proc() {.closure.} = echo "f3")
+
+  for a in fs:
+    a.fn(a.env)
+
+main()
+