diff --git a/.gitignore b/.gitignore
index d345406..996b2c7 100644
--- a/.gitignore
+++ b/.gitignore
@@ -5,3 +5,4 @@
 /yosys_0.9-1.debian.tar.xz
 /yosys-9cdc6b5.tar.gz
 /yosys-26e01a6.tar.gz
+/yosys-df2b79c.tar.gz
diff --git a/sources b/sources
index c343ae2..0b2fefd 100644
--- a/sources
+++ b/sources
@@ -1,2 +1,2 @@
-SHA512 (yosys-26e01a6.tar.gz) = 3c6b1927a2ea9ffbba9e9c9fcb79dd07968b3a1aabf970bc978bc3041c4fad0ddf5c2ac788dcc79bed89402ca76110460735284d1444be5e451c8e79c718773b
+SHA512 (yosys-df2b79c.tar.gz) = 02f0774ec0e3a0a83f8679c61ba138386254c109988392519d9b6ca354da6fa0702be625e764cad320b4dd0966b4ec8a2f5aa59b9720bb5a620d3678fecc0d8b
 SHA512 (yosys_0.9-1.debian.tar.xz) = d9df5637efc730b2b681daa8a5933803dba70dca5b31fe4ac13601032eccd9105c001563cf627fbdd2d4ebad8551f2647e882fbf107a7df98badb2d200e2b4dc
diff --git a/yosys.spec b/yosys.spec
index 7c05f3a..a6b026d 100644
--- a/yosys.spec
+++ b/yosys.spec
@@ -1,13 +1,13 @@
-%global commit0 26e01a67db4135196b1d25ed89e9e6ceb536f4e3
+%global commit0 df2b79ca7687ae46360084f2e3ef27222bb3a640
 %global shortcommit0 %%(c=%%{commit0}; echo ${c:0:7})
 
-%global snapdate 20210310
+%global snapdate 20210523
 
 %global __python %{__python3}
 
 Name:           yosys
 Version:        0.9
-Release:        11.%{snapdate}git%{shortcommit0}%{?dist}
+Release:        12.%{snapdate}git%{shortcommit0}%{?dist}
 Summary:        Yosys Open SYnthesis Suite, including Verilog synthesizer
 License:        ISC and MIT
 URL:            http://www.clifford.at/yosys/
@@ -169,6 +169,9 @@ make test ABCEXTERNAL=%{_bindir}/abc SEED=314159265359
 
 
 %changelog
+* Sun May 23 2021 Gabriel Somlo <gsomlo@gmail.com> - 0.9.12.20210523gitdf2b79c
+- update snapshot
+
 * Wed Mar 10 2021 Gabriel Somlo <gsomlo@gmail.com> - 0.9-11.20210310git26e01a6
 - exclude arch s390x (abc use broken on all Big Endian CPUs, see BZ 1937362, 1937395)