diff --git a/ChangeLog b/ChangeLog
index bc04314..b53f922 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -160,6 +160,8 @@ III).
 44. Fix bug in RunTest.bat for new test 14, and adjust the script for the added 
 test (there are now 20 in total).
 
+45. Fixed a corner case of range optimization in JIT.
+
 
 Version 10.20 30-June-2015
 --------------------------
diff --git a/src/pcre2_jit_compile.c b/src/pcre2_jit_compile.c
index 3bfb834..21b5a40 100644
--- a/src/pcre2_jit_compile.c
+++ b/src/pcre2_jit_compile.c
@@ -4997,8 +4997,10 @@ switch(length)
   case 4:
   if ((ranges[1] - ranges[0]) == (ranges[3] - ranges[2])
       && (ranges[0] | (ranges[2] - ranges[0])) == ranges[2]
+      && (ranges[1] & (ranges[2] - ranges[0])) == 0
       && is_powerof2(ranges[2] - ranges[0]))
     {
+    SLJIT_ASSERT((ranges[0] & (ranges[2] - ranges[0])) == 0 && (ranges[2] & ranges[3] & (ranges[2] - ranges[0])) != 0);
     OP2(SLJIT_OR, TMP1, 0, TMP1, 0, SLJIT_IMM, ranges[2] - ranges[0]);
     if (ranges[2] + 1 != ranges[3])
       {
diff --git a/src/pcre2_jit_test.c b/src/pcre2_jit_test.c
index 6c9f68b..98bb964 100644
--- a/src/pcre2_jit_test.c
+++ b/src/pcre2_jit_test.c
@@ -188,6 +188,7 @@ static struct regression_test_case regression_test_cases[] = {
 	{ CMUP, A, 0, 0, "\xf0\x90\x90\x80{2}", "\xf0\x90\x90\x80#\xf0\x90\x90\xa8\xf0\x90\x90\x80" },
 	{ CMUP, A, 0, 0, "\xf0\x90\x90\xa8{2}", "\xf0\x90\x90\x80#\xf0\x90\x90\xa8\xf0\x90\x90\x80" },
 	{ CMUP, A, 0, 0, "\xe1\xbd\xb8\xe1\xbf\xb8", "\xe1\xbf\xb8\xe1\xbd\xb8" },
+	{ M, A, 0, 0, "[3-57-9]", "5" },
 
 	/* Assertions. */
 	{ MU, A, 0, 0, "\\b[^A]", "A_B#" },