diff --git a/Makefile b/Makefile
index 44d064896..e268a4281 100644
--- a/Makefile
+++ b/Makefile
@@ -128,7 +128,7 @@ bumpversion:
 # is just a symlink to your actual ABC working directory, as 'make mrproper'
 # will remove the 'abc' directory and you do not want to accidentally
 # delete your work on ABC..
-ABCREV = 02393a2
+ABCREV = c4b12fa
 ABCPULL = 1
 ABCURL ?= https://github.com/berkeley-abc/abc
 ABCMKARGS = CC="$(CXX)" CXX="$(CXX)" ABC_USE_LIBSTDCXX=1