diff --git a/VERSION b/VERSION
index 24f3d6d..f03a6db 100644
--- a/VERSION
+++ b/VERSION
@@ -1,2 +1,2 @@
-2022 February 22 2022
+2022 March 20 2022
 
diff --git a/doc/CHANGES b/doc/CHANGES
index 490757f..70bf294 100644
--- a/doc/CHANGES
+++ b/doc/CHANGES
@@ -14661,4 +14661,43 @@ if (strstr(line,"%%begintext") != NULL) {
 which returns the pointer to %%begintext in the line.
 
 
+March 20 2022
+
+abc2midi bug: I could not demonstrate this bug on my own system.
+
+When abc2midi is compiled on a Debian linux system using the -O2 compilation
+flag (by default), it produces a faulty midi file for abc files containing
+gchords. Here is a sample file.
+
+%abc-2.2
+X:1
+T:Test
+M:C
+L:1/4
+Q:1/4=135
+V:S clef=treble
+V:s clef=treble
+K:C
+%%score (s S)
+%
+[V:s] "C" x2 "a" x2 |
+[V:S]  C  C   A A   |
+
+The problem occurs with the bass accompaniment generated by "a". The
+bass accompaniment creates a long string of A,, notes.
+
+This problem disappears when abc2midi is compiled without the
+-O2 optimizer.
+
+Analysis: the bug was traced to the code gchord_configure in genmidi.c.
+The limit of the loops
+ for (j=0; j<chordlen[chordnum]; j++)
+contain bad data when chordnum is set to -1 (for bass accompaniment).
+
+Fix: exit from gchord_configure function when chordnum is less than
+zero.
+
+The problem was identified to me by Jakob Englhauser. Jakob verified
+that this fix works.
+
 
diff --git a/doc/readme.txt b/doc/readme.txt
index 7756d3e..3b5e2f9 100644
--- a/doc/readme.txt
+++ b/doc/readme.txt
@@ -1,7 +1,7 @@
 abcMIDI :   abc <-> MIDI conversion utilities
 
 midi2abc version 3.52 March 04 2022
-abc2midi version 4.69 February 22 2022
+abc2midi version 4.70 March 20 2022
 abc2abc  version 2.16 February 22 2022
 yaps     version 1.88 February 22 2022
 abcmatch version 1.80 November 25 2021
diff --git a/genmidi.c b/genmidi.c
index c9d75f6..134cef4 100644
--- a/genmidi.c
+++ b/genmidi.c
@@ -358,7 +358,9 @@ void configure_gchord()
 {
  int j;
  int inchord, note;
+
  gchordnotes_size = 0;
+ if (chordnum < 0) return; /* [SS] 2022-03-20 */
 
 inchord = 0;
 if (inversion != -1) {
diff --git a/store.c b/store.c
index c8a58ea..48f197c 100644
--- a/store.c
+++ b/store.c
@@ -186,7 +186,7 @@ int main()
 
 */
 
-#define VERSION "4.70 February 22 2022 abc2midi" 
+#define VERSION "4.71 March 20 2022 abc2midi" 
 
 /* enables reading V: indication in header */
 #define XTEN1 1
@@ -1860,7 +1860,7 @@ nmidicmd++;
 /* [SS] 2015-06-01 For converting the %%MIDIx command to a
    %%MIDI command
 */
-void event_midi();
+void event_midi(char* s);  /* [SS] 2022-03-19 */
 
 
 void process_midix(s)