adds a test case (#24518)

closes #19698

tests/vm/tconst.nim

@@ -54,5 +54,33 @@ template main() =
       doAssert c == "foo"
 
 
+  when not defined(js):
+    block: # bug #19698
+      type
+        FormatInfo = object
+          readproc: ReadProc
+          writeproc: WriteProc
+
+        ReadProc = proc (s: pointer)
+        WriteProc = proc (s: pointer)
+
+      func initFormatInfo(readproc: ReadProc, writeproc: WriteProc = nil): FormatInfo {.compileTime.} =
+        result = FormatInfo(readproc: readproc, writeproc: nil)
+
+      proc readSampleImage(s: pointer) = discard
+
+      const SampleFormatInfo = initFormatInfo(readproc = readSampleImage)
+
+      const KnownFormats = [SampleFormatInfo]
+
+      func sortedFormatInfos(): array[len KnownFormats, FormatInfo] {.compileTime.} =
+        result = default(array[len KnownFormats, FormatInfo])
+        for i, info in KnownFormats:
+          result[i] = info
+
+      const SortedFormats = sortedFormatInfos()
+
+      discard SortedFormats
+
 static: main()
 main()