Set -Wunused and -Wsign-compare also when building with gcc

CMakeLists.txt

@@ -92,7 +92,7 @@ set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -DKokkos=InlineKokkos")
 
 #------------------------------------------------------
 # Pugs default compiler flags
-set(PUGS_CXX_FLAGS "${PUGS_CXX_FLAGS} -Wall -Wextra -pedantic -Wshadow")
+set(PUGS_CXX_FLAGS "${PUGS_CXX_FLAGS} -Wall -Wextra -pedantic -Wshadow -Wsign-compare -Wunused")
 
 if (CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
   if(CMAKE_CXX_COMPILER_VERSION VERSION_LESS "${GNU_CXX_MIN_VERSION}")
@@ -102,7 +102,7 @@ elseif(CMAKE_CXX_COMPILER_ID STREQUAL "Clang")
   if(CMAKE_CXX_COMPILER_VERSION VERSION_LESS "${CLANG_CXX_MIN_VERSION}")
     message(FATAL_ERROR "Pugs build requires at least llvm/clang ++-${CLANG_CXX_MIN_VERSION}")
   endif()
-  set(PUGS_CXX_FLAGS "${PUGS_CXX_FLAGS} -Wsign-compare -Wunused -Wunused-member-function -Wunused-private-field")
+  set(PUGS_CXX_FLAGS "${PUGS_CXX_FLAGS}  -Wunused-member-function -Wunused-private-field")
 endif()
 
 #------------------------------------------------------