Compiler settings

all result in below, as does adding -Wpedantic to the plug ins makefile as I did earlier:

$ RACK_DIR=C:/Users/ingo/Documents/g/Rack-SDK make install
g++  -std=c++11 -Wsuggest-override  -Wpedantic -fPIC -IC:/Users/ingo/Documents/g/Rack-SDK/include -IC:/Users/ingo/Documents/g/Rack-SDK/dep/include -MMD -MP -g -O3 -march=nocona -funsafe-math-optimizations -Wall -Wextra -Wno-unused-parameter -DARCH_WIN -D_USE_MATH_DEFINES  -c -o build/src/Bezosc.cpp.o src/Bezosc.cpp
In file included from C:/Users/ingo/Documents/g/Rack-SDK/include/window.hpp:11,
                 from C:/Users/ingo/Documents/g/Rack-SDK/include/rack.hpp:13,
                 from src/plugin.hpp:2,
                 from src/Bezosc.cpp:1:
C:/Users/ingo/Documents/g/Rack-SDK/dep/include/nanovg.h:40:3: warning: ISO C++ prohibits anonymous structs [-Wpedantic]
   40 |   };
      |   ^
In file included from C:/Users/ingo/Documents/g/Rack-SDK/include/ui/common.hpp:4,
                 from C:/Users/ingo/Documents/g/Rack-SDK/include/ui/MenuOverlay.hpp:3,
                 from C:/Users/ingo/Documents/g/Rack-SDK/include/helpers.hpp:3,
                 from C:/Users/ingo/Documents/g/Rack-SDK/include/rack.hpp:16,
                 from src/plugin.hpp:2,
                 from src/Bezosc.cpp:1:
C:/Users/ingo/Documents/g/Rack-SDK/dep/include/blendish.h:1094:2: warning: extra ';' [-Wpedantic]
 1094 | };
      |  ^
k-SDK -lRack
rm -rf dist
mkdir -p dist/"Bezosc"
cp plugin.dll dist/"Bezosc"/
strip -s dist/"Bezosc"/plugin.dll
cp -r --parents res  plugin.json dist/"Bezosc"/
cd dist && zip -q -9 -r "Bezosc"-"1.0.0" "Bezosc"
cp dist/"Bezosc"-"1.0.0" "C:\Users\ingo"/Documents/Rack/plugins-v1/

So I checked also - and you must add it to FLAGS in of Rack or to the Makefile of the plugin you compile itself.

But as far is see in your output pedantic warning are printed, so it works.

C:/Users/ingo/Documents/g/Rack-SDK/dep/include/blendish.h:1094:2: warning: extra ';' [-Wpedantic] ...

When i add for example -Wpedantic for the Fundamental plugin here - it prints pedantic warnings for plugin build, e.g:

g++ -std=c++11 -Wsuggest-override  -Idep/include -Wpedantic -fPIC  -I../../include -I../../dep/include -MMD -MP -g -O3 -march=nocona -funsafe-math-optimizations -Wall -Wextra -Wno-unused-parameter -DARCH_LIN  -c -o build/src/Viz.cpp.o src/Viz.cpp
In file included from ../../include/window.hpp:11:0,
                 from ../../include/rack.hpp:13,
                 from src/plugin.hpp:1,
                 from src/Viz.cpp:1:
../../dep/include/nanovg.h:40:3: warning: ISO C++ prohibits anonymous structs [-Wpedantic]

Thanks @qno