check gcc 11 behavior

Author: ospencer

dune

@@ -40,7 +40,7 @@
      -G
      "Unix Makefiles"
      ; GCC 7 (shipped with esy) doesn't like _ for unused variables
-     "-DCMAKE_CXX_FLAGS=-Wno-unused-variable -Wno-maybe-uninitialized"
+     ; "-DCMAKE_CXX_FLAGS=-Wno-unused-variable -Wno-maybe-uninitialized"
      -DBUILD_TESTS=OFF
      -DBUILD_TOOLS=OFF
      -DBUILD_STATIC_LIB=ON
@@ -127,7 +127,7 @@
      "Unix Makefiles"
      -DCMAKE_C_COMPILER=x86_64-w64-mingw32-gcc
      -DCMAKE_CXX_COMPILER=x86_64-w64-mingw32-g++
-     "-DCMAKE_SYSTEM_NAME=Windows" 
+     "-DCMAKE_SYSTEM_NAME=Windows"
      ; GCC 7 (shipped with esy) doesn't like _ for unused variables
      "-DCMAKE_CXX_FLAGS=-Wno-unused-variable -Wno-maybe-uninitialized"
      -DBUILD_TESTS=OFF