From afb5212fe04a3e38b4582f70c544f9df6bb0994b Mon Sep 17 00:00:00 2001
From: cooldome <ariabushenko@gmail.com>
Date: Tue, 27 Oct 2020 23:09:26 +0000
Subject: [PATCH] fix #15752 (#15754)

(cherry picked from commit f8cac6bbbcfa8ddc649160945a17a6f5b7a4d9d6)
---
 compiler/sizealignoffsetimpl.nim | 8 ++++----
 tests/enum/tenum.nim             | 9 +++++++++
 2 files changed, 13 insertions(+), 4 deletions(-)

diff --git a/compiler/sizealignoffsetimpl.nim b/compiler/sizealignoffsetimpl.nim
index 3e536f5d7c..2c764fe12a 100644
--- a/compiler/sizealignoffsetimpl.nim
+++ b/compiler/sizealignoffsetimpl.nim
@@ -277,14 +277,14 @@ proc computeSizeAlign(conf: ConfigRef; typ: PType) =
       typ.size = 4              # use signed int32
       typ.align = 4
     else:
-      let length = toInt64(lastOrd(conf, typ))   # BUGFIX: use lastOrd!
-      if length + 1 < `shl`(1, 8):
+      let lastOrd = toInt64(lastOrd(conf, typ))   # BUGFIX: use lastOrd!
+      if lastOrd < `shl`(1, 8):
         typ.size = 1
         typ.align = 1
-      elif length + 1 < `shl`(1, 16):
+      elif lastOrd < `shl`(1, 16):
         typ.size = 2
         typ.align = 2
-      elif length + 1 < `shl`(BiggestInt(1), 32):
+      elif lastOrd < `shl`(BiggestInt(1), 32):
         typ.size = 4
         typ.align = 4
       else:
diff --git a/tests/enum/tenum.nim b/tests/enum/tenum.nim
index 8cc578d3cc..aa338ee2c0 100644
--- a/tests/enum/tenum.nim
+++ b/tests/enum/tenum.nim
@@ -154,3 +154,12 @@ block nonzero: # bug #6959
     B
     C
   let slice = SomeEnum.low..SomeEnum.high
+
+block size_one_byte: #issue 15752
+  type
+    Flag = enum
+      Disabled = 0x00
+      Enabled = 0xFF
+
+  static:
+    assert 1 == sizeof(Flag)
\ No newline at end of file