Fixed compatibility with Ubuntu 18.04

Author: drowaudio

.github/workflows/build.yaml

@@ -18,7 +18,7 @@ jobs:
       matrix:
         include:
           - name: Linux
-            os: ubuntu-22.04
+            os: ubuntu-18.04
             app: pluginval
             test-binary: ./pluginval
           - name: macOS
@@ -97,7 +97,7 @@ jobs:
         with: 
           path: ${{ env.PLUGIN_CACHE_PATH }}
           # Increment the version in the key below to manually break plugin cache
-          key: v6-${{ runner.os }}-${{ env.JUCE_SHA1 }}
+          key: v7-${{ runner.os }}-${{ env.JUCE_SHA1 }}
 
       - name: Build JUCE example plugins
         if: steps.cache-plugins.outputs.cache-hit != 'true'

CMakeLists.txt

@@ -86,3 +86,8 @@ target_link_libraries(pluginval PRIVATE
     juce::juce_audio_processors
     juce::juce_audio_utils
     juce::juce_recommended_warning_flags)
+
+if (${CMAKE_SYSTEM_NAME} MATCHES "Linux")
+    target_link_libraries(pluginval PRIVATE
+        -static-libstdc++)
+endif()