From 43191e7e799237b0ebf2ae115a0f74e023fb245d Mon Sep 17 00:00:00 2001
From: whitequark <cz@m-labs.hk>
Date: Mon, 26 Aug 2019 09:35:37 +0000
Subject: [PATCH] back.verilog: bump Yosys version requirement to 0.9.

Fixes #55.
---
 nmigen/back/verilog.py | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/nmigen/back/verilog.py b/nmigen/back/verilog.py
index 85a7d44..2552df0 100644
--- a/nmigen/back/verilog.py
+++ b/nmigen/back/verilog.py
@@ -23,14 +23,14 @@ def _yosys_version():
             raise YosysError("Could not find Yosys in PATH. Place `yosys` in PATH or specify "
                              "path explicitly via the YOSYS environment variable") from e
 
-    m = re.match(r"^Yosys ([\d.]+)\+(\d+)", version)
-    tag, offset = m[1], m[2]
+    m = re.match(r"^Yosys ([\d.]+)(?:\+(\d+))?", version)
+    tag, offset = m[1], m[2] or 0
     return tuple(map(int, tag.split("."))), offset
 
 
 def _convert_il_text(il_text, strip_src):
     version, offset = _yosys_version()
-    if version < (0, 8):
+    if version < (0, 9):
         raise YosysError("Yosys %d.%d is not suppored", *version)
 
     attr_map = []
@@ -42,7 +42,7 @@ def _convert_il_text(il_text, strip_src):
 read_ilang <<rtlil
 {}
 rtlil
-proc_prune
+{prune}proc_prune
 proc_init
 proc_arst
 proc_dff
@@ -50,7 +50,8 @@ proc_clean
 memory_collect
 attrmap {}
 write_verilog -norename
-""".format(il_text, " ".join(attr_map))
+""".format(il_text, " ".join(attr_map),
+           prune="# " if version == (0, 9) and offset == 0 else "")
 
     popen = subprocess.Popen([os.getenv("YOSYS", "yosys"), "-q", "-"],
         stdin=subprocess.PIPE,
-- 
2.30.2