ci/make: add basic CI for mac/linux, fix compilation for latest SDK 2.4.1

.github/workflows/main.yml

@@ -0,0 +1,36 @@
+name: build
+
+on: [push]
+
+jobs:
+  ubuntu-build:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: YosysHQ/setup-oss-cad-suite@v3
+      - run: verilator --version
+      - run: wget https://vcvrack.com/downloads/Rack-SDK-2.4.1-lin-x64.zip
+      - run: unzip Rack-SDK*.zip && rm Rack-SDK*.zip
+      - run: make RACK_DIR=`pwd`/Rack-SDK
+      - uses: actions/upload-artifact@v4
+        with:
+          name: plugin-lin-x64
+          path: |
+            plugin.so
+            plugin.json
+
+  macos-build:
+    runs-on: macos-latest
+    steps:
+      - uses: actions/checkout@v4
+      - run: brew install verilator
+      - run: verilator --version
+      - run: wget https://vcvrack.com/downloads/Rack-SDK-2.4.1-mac-x64.zip
+      - run: unzip Rack-SDK*.zip && rm Rack-SDK*.zip
+      - run: make RACK_DIR=`pwd`/Rack-SDK
+      - uses: actions/upload-artifact@v4
+        with:
+          name: plugin-mac-x64
+          path: |
+            plugin.so
+            plugin.json

Makefile

@@ -10,16 +10,15 @@ VERILATED_OBJ=Vcore__ALL.a
 
 # FLAGS will be passed to both the C and C++ compiler
 FLAGS += -I$(VERILATOR_ROOT)/include -faligned-new
-CFLAGS +=
-CXXFLAGS +=
 
 # Careful about linking to shared libraries, since you can't assume much about the user's environment and library search path.
 # Static libraries are fine, but they should be added to this plugin's build system.
-#LDFLAGS += -L$(VERILATED_PATH) -l:$(VERILATED_OBJ)
 OBJECTS += $(VERILATED_PATH)/$(VERILATED_OBJ)
 
 # Add .cpp files to the build
-SOURCES += $(wildcard src/*.cpp) $(VERILATOR_ROOT)/include/verilated.cpp
+SOURCES += $(wildcard src/*.cpp) \
+		   $(VERILATOR_ROOT)/include/verilated.cpp \
+		   $(VERILATOR_ROOT)/include/verilated_threads.cpp
 
 # Add files to the ZIP package when running `make dist`
 # The compiled plugin and "plugin.json" are automatically added.
@@ -38,3 +37,6 @@ src/eurorack-pmod.cpp: $(VERILATED_PATH)/$(VERILATED_OBJ)
 
 # Include the Rack plugin Makefile framework
 include $(RACK_DIR)/plugin.mk
+
+CXXFLAGS := $(filter-out -std=c++11,$(CXXFLAGS))
+CXXFLAGS += -std=c++17

README.md

@@ -1,3 +1,5 @@
+![ci workflow](https://github.com/apfelaudio/verilog-vcvrack/actions/workflows/main.yml/badge.svg)
+
 # Basic example of simulating Verilog inside a VCV Rack plugin.
 
 This plugin simulates the panel layout of the [`eurorack-pmod`](https://github.com/schnommus/eurorack-pmod) FPGA-based module. See [`rtl/core.sv`](rtl/core.sv) for the Verilog source. This example is intentionally kept as simple as possible.
@@ -30,3 +32,21 @@ This plugin should now be visible on restarting VCV Rack.
 # Limitations
 
 At the moment only the audio rate `sample_clk` is injected into the verilog core, I doubt verilator would be fast enough to simulate filters pipelined at the PLL clock (12MHz/24MHz).
+
+# Debugging
+
+Some basic CI for Mac + Linux is in [`.github/workflows/main.yml`](.github/workflows/main.yml), this may be useful to look at if you are having trouble building.
+
+Sometimes it is useful to run VCVRack in development mode so that you get some more detailed logs if a plugin doesn't load correctly:
+
+```bash
+$ ./Rack --dev
+```
+
+For example, an update to verilator recently added an extra source dependency that was missing, causing an error like this --
+
+
+```bash
+[0.011 info src/plugin.cpp:130 loadPlugin] Loading plugin from /home/seb/Downloads/Rack2Free/plugins/eurorack-pmod-vcvrack
+[0.011 warn src/plugin.cpp:196 loadPlugin] Could not load plugin /home/seb/Downloads/Rack2Free/plugins/eurorack-pmod-vcvrack: Failed to load library /home/seb/Downloads/Rack2Free/plugins/eurorack-pmod-vcvrack/plugin.so: /home/seb/Downloads/Rack2Free/plugins/eurorack-pmod-vcvrack/plugin.so: undefined symbol: _ZN12VlThreadPoolC1EP16VerilatedContextj
+```