Overhaul compiler warnings infrastructure

* Track our warnings separate from normal flags
* Remove all warnings from the SWIG code
* Add more GCC warnings

CMakeLists.txt

@@ -302,11 +302,6 @@ if( CMAKE_COMPILER_IS_GNUCXX OR CMAKE_CXX_COMPILER_ID MATCHES "Clang" )
         set( CMAKE_CXX_FLAGS "-ffloat-store ${CMAKE_CXX_FLAGS}" )
     endif()
 
-    # Establish -Wall early, so specialized relaxations of this may come
-    # subsequently on the command line, such as in pcbnew/github/CMakeLists.txt
-    set( CMAKE_C_FLAGS   "-Wall ${CMAKE_C_FLAGS}" )
-    set( CMAKE_CXX_FLAGS "-Wall ${CMAKE_CXX_FLAGS}" )
-
     # Link flags in Debug: -g1 and -ggdb1 or -g1 and -ggdb3 can be used.
     # Level 1 produces minimal information, enough for making basic backtraces.
     # This includes descriptions of functions and external variables, and line number tables,

CMakeModules/Warnings.cmake

@@ -26,11 +26,23 @@ if( CMAKE_COMPILER_IS_GNUCXX OR CMAKE_CXX_COMPILER_ID MATCHES "Clang" )
     include( CheckCXXCompilerFlag )
 
 
+    # The SWIG-generated files tend to throw a lot of warnings, so
+    # we do not add the warnings directly to the flags here but instead
+    # keep track of them and add them to the flags later in a controlled manner
+    # (that way we can not put any warnings on the SWIG-generated files)
+    set( COMPILER_SUPPORTS_WARNINGS TRUE )
+
+    # Establish -Wall early, so specialized relaxations of this may come
+    # subsequently on the command line, such as in pcbnew/github/CMakeLists.txt
+    set( WARN_FLAGS_C   "-Wall" )
+    set( WARN_FLAGS_CXX "-Wall" )
+
+
     # Warn about missing override specifiers
     CHECK_CXX_COMPILER_FLAG( "-Wsuggest-override" COMPILER_SUPPORTS_WSUGGEST_OVERRIDE )
 
     if( COMPILER_SUPPORTS_WSUGGEST_OVERRIDE )
-        set( CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wsuggest-override" )
+        set( WARN_FLAGS_CXX "${WARN_FLAGS_CXX} -Wsuggest-override" )
         message( STATUS "Enabling warning -Wsuggest-override" )
     endif()
 
@@ -39,15 +51,34 @@ if( CMAKE_COMPILER_IS_GNUCXX OR CMAKE_CXX_COMPILER_ID MATCHES "Clang" )
     CHECK_CXX_COMPILER_FLAG( "-Winconsistent-missing-override" COMPILER_SUPPORTS_WINCONSISTENT_MISSING_OVERRIDE )
 
     if( COMPILER_SUPPORTS_WINCONSISTENT_MISSING_OVERRIDE )
-        set( CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Winconsistent-missing-override" )
+        set( WARN_FLAGS_CXX "${WARN_FLAGS_CXX} -Winconsistent-missing-override" )
         message( STATUS "Enabling warning -Winconsistent-missing-override" )
     endif()
 
 
+    # Warn on duplicated branches
+    CHECK_CXX_COMPILER_FLAG( "-Wduplicated-branches" COMPILER_SUPPORTS_WDUPLICATED_BRANCHES )
+
+    if( COMPILER_SUPPORTS_WDUPLICATED_BRANCHES )
+        set( WARN_FLAGS_CXX "${WARN_FLAGS_CXX} -Wduplicated-branches" )
+        message( STATUS "Enabling warning -Wduplicated-branches" )
+    endif()
+
+
+    # Warn on duplicated conditions
+    CHECK_CXX_COMPILER_FLAG( "-Wduplicated-cond" COMPILER_SUPPORTS_WDUPLICATED_COND )
+
+    if( COMPILER_SUPPORTS_WDUPLICATED_COND )
+        set( WARN_FLAGS_CXX "${WARN_FLAGS_CXX} -Wduplicated-cond" )
+        message( STATUS "Enabling warning -Wduplicated-cond" )
+    endif()
+
+
+
     CHECK_CXX_COMPILER_FLAG( "-Wvla" COMPILER_SUPPORTS_WVLA )
 
     if( COMPILER_SUPPORTS_WVLA )
-        set( CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Werror=vla" )
+        set( WARN_FLAGS_CXX "${WARN_FLAGS_CXX} -Werror=vla" )
         message( STATUS "Enabling error for -Wvla" )
     endif()
 
@@ -56,7 +87,13 @@ if( CMAKE_COMPILER_IS_GNUCXX OR CMAKE_CXX_COMPILER_ID MATCHES "Clang" )
     CHECK_CXX_COMPILER_FLAG( "-Wimplicit-fallthrough" COMPILER_SUPPORTS_WIMPLICIT_FALLTHROUGH )
 
     if( COMPILER_SUPPORTS_WIMPLICIT_FALLTHROUGH )
-        set( CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wimplicit-fallthrough" )
+        if( CMAKE_COMPILER_IS_GNUCXX )
+            # GCC level 5 does not allow comments - mirrors the Clang warning
+            set( WARN_FLAGS_CXX "${WARN_FLAGS_CXX} -Wimplicit-fallthrough=5" )
+        else()
+            set( WARN_FLAGS_CXX "${WARN_FLAGS_CXX} -Wimplicit-fallthrough" )
+        endif()
+
         message( STATUS "Enabling warning -Wimplicit-fallthrough" )
     endif()
 
@@ -65,20 +102,16 @@ if( CMAKE_COMPILER_IS_GNUCXX OR CMAKE_CXX_COMPILER_ID MATCHES "Clang" )
     CHECK_CXX_COMPILER_FLAG( "-Wreturn-type" COMPILER_SUPPORTS_WRETURN_TYPE )
 
     if( COMPILER_SUPPORTS_WRETURN_TYPE )
-        set( CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Werror=return-type" )
+        set( WARN_FLAGS_CXX "${WARN_FLAGS_CXX} -Werror=return-type" )
         message( STATUS "Enabling error for -Wreturn-type" )
     endif()
 
 
-    # Warn about shadowed variables (-Wshadow option), if supported
-    # Unfortunately, the swig autogenerated files have a lot of shadowed variables
-    # and -Wno-shadow does not exist.
-    # Adding -Wshadow can be made only for .cpp files
-    # and will be added later in CMakeLists.txt
+    # Warn about shadowed variables
     CHECK_CXX_COMPILER_FLAG( "-Wshadow" COMPILER_SUPPORTS_WSHADOW )
 
     if( COMPILER_SUPPORTS_WSHADOW )
-        set( WSHADOW_FLAGS "-Wshadow" )
+        set( WARN_FLAGS_CXX "${WARN_FLAGS_CXX} -Wshadow" )
         message( STATUS "Enabling warning -Wshadow" )
     endif()
 

bitmap2component/CMakeLists.txt

@@ -1,6 +1,7 @@
-# .cpp files are compiled with extra ${WSHADOW_FLAGS}
-if( COMPILER_SUPPORTS_WSHADOW )
-    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${WSHADOW_FLAGS}")
+# Add all the warnings to the files
+if( COMPILER_SUPPORTS_WARNINGS )
+    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${WARN_FLAGS_CXX}")
+    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${WARN_FLAGS_C}")
 endif()
 
 add_definitions( -DBITMAP_2_CMP )

common/CMakeLists.txt

@@ -1,6 +1,7 @@
-# .cpp files are compiled with extra ${WSHADOW_FLAGS}
-if( COMPILER_SUPPORTS_WSHADOW )
-    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${WSHADOW_FLAGS}")
+# Add all the warnings to the files
+if( COMPILER_SUPPORTS_WARNINGS )
+    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${WARN_FLAGS_CXX}")
+    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${WARN_FLAGS_C}")
 endif()
 
 add_subdirectory( libeval )

cvpcb/CMakeLists.txt

@@ -1,6 +1,7 @@
-# .cpp files are compiled with extra ${WSHADOW_FLAGS}
-if( COMPILER_SUPPORTS_WSHADOW )
-    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${WSHADOW_FLAGS}")
+# Add all the warnings to the files
+if( COMPILER_SUPPORTS_WARNINGS )
+    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${WARN_FLAGS_CXX}")
+    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${WARN_FLAGS_C}")
 endif()
 
 add_definitions( -DCVPCB )

eeschema/CMakeLists.txt

@@ -1,6 +1,7 @@
-# .cpp files are compiled with extra ${WSHADOW_FLAGS}
-if( COMPILER_SUPPORTS_WSHADOW )
-    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${WSHADOW_FLAGS}")
+# Add all the warnings to the files
+if( COMPILER_SUPPORTS_WARNINGS )
+    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${WARN_FLAGS_CXX}")
+    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${WARN_FLAGS_C}")
 endif()
 
 add_definitions( -DEESCHEMA )

gerbview/CMakeLists.txt

@@ -1,6 +1,7 @@
-# .cpp files are compiled with extra ${WSHADOW_FLAGS}
-if( COMPILER_SUPPORTS_WSHADOW )
-    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${WSHADOW_FLAGS}")
+# Add all the warnings to the files
+if( COMPILER_SUPPORTS_WARNINGS )
+    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${WARN_FLAGS_CXX}")
+    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${WARN_FLAGS_C}")
 endif()
 
 add_definitions(-DGERBVIEW)

kicad/CMakeLists.txt

@@ -1,6 +1,7 @@
-# .cpp files are compiled with extra ${WSHADOW_FLAGS}
-if( COMPILER_SUPPORTS_WSHADOW )
-    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${WSHADOW_FLAGS}")
+# Add all the warnings to the files
+if( COMPILER_SUPPORTS_WARNINGS )
+    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${WARN_FLAGS_CXX}")
+    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${WARN_FLAGS_C}")
 endif()
 
 add_definitions( -DKICAD )

pagelayout_editor/CMakeLists.txt

@@ -1,6 +1,7 @@
-# .cpp files are compiled with extra ${WSHADOW_FLAGS}
-if( COMPILER_SUPPORTS_WSHADOW )
-    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${WSHADOW_FLAGS}")
+# Add all the warnings to the files
+if( COMPILER_SUPPORTS_WARNINGS )
+    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${WARN_FLAGS_CXX}")
+    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${WARN_FLAGS_C}")
 endif()
 
 add_definitions(-DPL_EDITOR)

pcbnew/CMakeLists.txt

@@ -359,36 +359,29 @@ set( PCBNEW_SCRIPTING_PYTHON_HELPERS
     swig/python_scripting.cpp
     )
 
-if( COMPILER_SUPPORTS_WSHADOW )
-    # .cpp files are compiled with extra ${WSHADOW_FLAGS}, but not .cxx files
+
+if( COMPILER_SUPPORTS_WARNINGS )
+    # Only compile our source files with the warnings, since the SWIG generated
+    # files contain a lot of warnings, we just ignore it.
     set_source_files_properties(
         ${PCBNEW_SRCS} ${PCBNEW_COMMON_SRCS} ${PCBNEW_SCRIPTING_DIALOGS} ${PCBNEW_SCRIPTING_PYTHON_HELPERS}
-        PROPERTIES COMPILE_FLAGS ${WSHADOW_FLAGS}
-    )
-
-    # There is a lot of 'local variable shadowed' warnings,
-    # but we have no control over the generated code
-    set_source_files_properties( pcbnew_wrap.cxx pcbnewPYTHON_wrap.cxx
-        PROPERTIES COMPILE_FLAGS -Wno-shadow
+        PROPERTIES COMPILE_FLAGS ${WARN_FLAGS_CXX}
     )
 endif()
 
 
 if( KICAD_SCRIPTING )
+
+    # Disable all warnings for the SWIG file
+    if( CMAKE_COMPILER_IS_GNUCXX OR CMAKE_CXX_COMPILER_ID MATCHES "Clang" )
+        set_source_files_properties( pcbnew_wrap.cxx PROPERTIES COMPILE_FLAGS "-Wno-everything" )
+    endif()
+
     set( PCBNEW_SCRIPTING_SRCS
         ${PCBNEW_SCRIPTING_DIALOGS}
         pcbnew_wrap.cxx
         ${PCBNEW_SCRIPTING_PYTHON_HELPERS}
         )
-
-
-    # Swig generated files do not use the override specifier, therefore
-    # disable suggest-override warnings
-    if( COMPILER_SUPPORTS_WSUGGEST_OVERRIDE )
-        set_source_files_properties( pcbnew_wrap.cxx pcbnewPYTHON_wrap.cxx
-            PROPERTIES COMPILE_FLAGS -Wno-suggest-override
-        )
-    endif()
 endif()
 
 

plugins/CMakeLists.txt

@@ -1,6 +1,7 @@
-# .cpp files are compiled with extra ${WSHADOW_FLAGS}
-if( COMPILER_SUPPORTS_WSHADOW )
-    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${WSHADOW_FLAGS}")
+# Add all the warnings to the files
+if( COMPILER_SUPPORTS_WARNINGS )
+    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${WARN_FLAGS_CXX}")
+    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${WARN_FLAGS_C}")
 endif()
 
 include_directories(

thirdparty/markdown2html/CMakeLists.txt

@@ -1,6 +1,7 @@
-# .cpp files are compiled with extra ${WSHADOW_FLAGS}
-if( COMPILER_SUPPORTS_WSHADOW )
-    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${WSHADOW_FLAGS}")
+# Add all the warnings to the files
+if( COMPILER_SUPPORTS_WARNINGS )
+    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${WARN_FLAGS_CXX}")
+    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${WARN_FLAGS_C}")
 endif()
 
 include_directories( BEFORE ${INC_BEFORE} ${INC_AFTER} )

utils/CMakeLists.txt

@@ -1,6 +1,7 @@
-# .cpp files are compiled with extra ${WSHADOW_FLAGS}
-if( COMPILER_SUPPORTS_WSHADOW )
-    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${WSHADOW_FLAGS}")
+# Add all the warnings to the files
+if( COMPILER_SUPPORTS_WARNINGS )
+    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${WARN_FLAGS_CXX}")
+    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${WARN_FLAGS_C}")
 endif()
 
 add_subdirectory( idftools )