Configure build to work with case fallthrough GCC7 warning. Refs #671

CMakeLists.txt

@@ -181,6 +181,12 @@ if(CMAKE_COMPILER_IS_GNUCXX OR CMAKE_CXX_COMPILER_ID MATCHES "Clang")
         -Wno-reorder)
     if(CMAKE_COMPILER_IS_GNUCXX)
         list(APPEND warning_flags -Wno-unused-but-set-variable)
+
+        # We keep the implicit fallthrough warning for now, but allow more
+        # comments to silence it.
+        if (CMAKE_CXX_COMPILER_VERSION VERSION_GREATER 7.0)
+            list(APPEND warning_flags -Wimplicit-fallthrough=2)
+        endif()
     endif()
 
     if(NOT CMAKE_BUILD_TYPE STREQUAL "Release")

qrenderdoc/CMakeLists.txt

@@ -114,6 +114,11 @@ file(WRITE
      "OSX_ICONFILE=${CMAKE_CURRENT_BINARY_DIR}/RenderDoc.icns\n")
 
 # propagate build version info. Lots of escaping needed here to pass ""s into the define value
+if(CMAKE_COMPILER_IS_GNUCXX)
+    file(APPEND
+        ${CMAKE_BINARY_DIR}/qrenderdoc/qrenderdoc_cmake.pri
+        "QMAKE_CXXFLAGS+=-Wno-unknown-warning -Wno-implicit-fallthrough\n")
+endif()
 
 file(APPEND
     ${CMAKE_BINARY_DIR}/qrenderdoc/qrenderdoc_cmake.pri

renderdoc/CMakeLists.txt

@@ -201,6 +201,11 @@ if(CMAKE_COMPILER_IS_GNUCXX OR CMAKE_CXX_COMPILER_ID MATCHES "Clang" OR APPLE)
     # -Wno-shift-negative-value available
     set_source_files_properties(3rdparty/jpeg-compressor/jpgd.cpp
         PROPERTIES COMPILE_FLAGS "-Wno-unknown-warning-option -Wno-shift-negative-value")
+
+    if(CMAKE_COMPILER_IS_GNUCXX)
+        set_property(SOURCE 3rdparty/jpeg-compressor/jpgd.cpp
+            APPEND_STRING PROPERTY COMPILE_FLAGS " -Wno-unknown-warning -Wno-implicit-fallthrough")
+    endif()
 endif()
 
 add_library(rdoc OBJECT ${sources})