diff --git a/CHANGELOG.md b/CHANGELOG.md
index 88008b1ce..3e47c9b79 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -97,6 +97,7 @@ Expected: Early March 2020
   
 ### Corrected Bugs
 
+* Fixed [Makefile syntax error *** mixed implicit and normal rules #104](https://github.com/clicon/clixon/issues/104). Make operator `|=` seems not to work on GNU make version < 4.
 * Yang specs with recursive grouping/use statement is now fixed: instead of stack overflow, you get an error message and an exit
 * Fixed: Some state data was sorted but should not have been.
   * Search function checked only own not for config false statement, should have checked all ancestors.
diff --git a/lib/src/Makefile.in b/lib/src/Makefile.in
index 07f1341df..9a60b7097 100644
--- a/lib/src/Makefile.in
+++ b/lib/src/Makefile.in
@@ -216,8 +216,9 @@ distclean: clean
 .c.o: $(GENSRC)
 	rm -f $@ && $(CC) $(INCLUDES) $(CPPFLAGS) $(CFLAGS) -c $<
 
-# Compute the length of the date command (and add some extra woith XXX)
-DATELEN != date +"%Y.%m.%d %H:%M by `whoami` on `hostname`XXXX"|wc -c
+# Compute the length of the date command (and add some extra with XXX)
+DATELEN = $(shell date +"%Y.%m.%d %H:%M by `whoami` on `hostname`XXXX"|wc -c)
+
 .PHONY: build.c
 build.c:	
 	date +"const char CLIXON_BUILDSTR[$(DATELEN)]=\"%Y.%m.%d %H:%M by `whoami` on `hostname`"\"\; > build.c;