diff --git a/VERSION b/VERSION
index 42f91b4..97d67e1 100644
--- a/VERSION
+++ b/VERSION
@@ -1,2 +1,2 @@
-2021 May 09 2021
+2021 May 10 2021
 
diff --git a/doc/CHANGES b/doc/CHANGES
index ed503ab..a79f7d6 100644
--- a/doc/CHANGES
+++ b/doc/CHANGES
@@ -14172,3 +14172,35 @@ to 1 when parseline() encounters "%%beginps" and is reset to 0
 when %%endps" is encountered. If ignore_line is 1, the rest of
 the code in parseline() is ignored when abc2midi is running.
 
+
+May 10 2020
+
+abc2midi: the following file causes a core dump.
+
+X:1
+T:Autumn Ale
+C:Chance Thomas, Stephen DiGregorio, Geoff Scott and/or Brad Spear
+R:Jig
+S:The Lord of the Rings Online Soundtrack
+O:Turbine's Middle Earth
+Z:Northman
+N:This is not intended for percussion instruments.
+Q:333
+M:6/8
+L:1/8
+K:D
+AGA BA/3B/3A/3G | FE/3F/3E/3D EFG |
+
+abc2midi notpowerof2.abc
+4.53 May 09 2021 abc2midi
+Error in line-char 13-5 : 3 b is not a power of 2
+Error in line-char 13-8 : 3 b is not a power of 2
+Floating point exception (core dumped)
+
+Analysis: the crash occurs in the function reduce (0)
+which cannot handle a division by zero. The function
+check_power_of_two(3) in parseabc.c returns 0 when the
+argument is not a power of 2. Fix: changed the return
+to -1. The program does not crash but the midi file
+is not created correctly.
+
diff --git a/doc/readme.txt b/doc/readme.txt
index 52e34ce..6059e8b 100644
--- a/doc/readme.txt
+++ b/doc/readme.txt
@@ -1,7 +1,7 @@
 abcMIDI :   abc <-> MIDI conversion utilities
 
 midi2abc version 3.47 November 01 2020
-abc2midi version 4.53 May 08 2021
+abc2midi version 4.54 May 10 2021
 abc2abc  version 2.13 May 08 2021
 yaps     version 1.86 December 10 2020
 abcmatch version 1.78 March 27 2021
diff --git a/parseabc.c b/parseabc.c
index 942c5ab..395705a 100644
--- a/parseabc.c
+++ b/parseabc.c
@@ -420,7 +420,7 @@ int check_power_of_two(int denom)
     if (t % 2 != 0) {
       snprintf(error_message, 80, "%d b is not a power of 2", denom);
       event_error (error_message);
-      return 0;
+      return -1;
     } else {
       t = t / 2;
     }
diff --git a/store.c b/store.c
index e40922b..d197fea 100644
--- a/store.c
+++ b/store.c
@@ -186,7 +186,7 @@ int main()
 
 */
 
-#define VERSION "4.53 May 09 2021 abc2midi" 
+#define VERSION "4.54 May 10 2021 abc2midi" 
 
 /* enables reading V: indication in header */
 #define XTEN1 1