diff --git a/3rdparty/python-console/ParseHelper.h b/3rdparty/python-console/ParseHelper.h
index d01e2627..e0fe9550 100644
--- a/3rdparty/python-console/ParseHelper.h
+++ b/3rdparty/python-console/ParseHelper.h
@@ -28,7 +28,7 @@ THE SOFTWARE.
 #include <memory>
 #include "ParseMessage.h"
 
-class ParseListener;
+struct ParseListener;
 
 /**
 Helps chunk lines of Python code into compilable statements.
@@ -94,7 +94,7 @@ public:
         // return if there was an error
         bool initializeIndent(const std::string& str);
     };
-    friend class BlockParseState;
+    friend struct BlockParseState;
 
     struct BracketParseState : public ParseState
     {
diff --git a/3rdparty/python-console/modified/pyconsole.cc b/3rdparty/python-console/modified/pyconsole.cc
index 186d74d2..d724553b 100644
--- a/3rdparty/python-console/modified/pyconsole.cc
+++ b/3rdparty/python-console/modified/pyconsole.cc
@@ -95,7 +95,7 @@ void PythonConsole::parseEvent( const ParseMessage& message )
     }
 
     // interpret valid user input
-    int errorCode;
+    int errorCode = 0;
     std::string res;
     if ( message.message.size() )
         res = pyinterpreter_execute( message.message, &errorCode );
diff --git a/3rdparty/python-console/modified/pyinterpreter.cc b/3rdparty/python-console/modified/pyinterpreter.cc
index ee8c4aa8..f53207ad 100644
--- a/3rdparty/python-console/modified/pyinterpreter.cc
+++ b/3rdparty/python-console/modified/pyinterpreter.cc
@@ -38,9 +38,9 @@ static std::list<std::string> m_suggestions;
 
 template <typename... Args> std::string string_format(const std::string &format, Args... args)
 {
-    size_t size = std::snprintf(nullptr, 0, format.c_str(), args...) + 1; // Extra space for '\0'
+    size_t size = snprintf(nullptr, 0, format.c_str(), args...) + 1; // Extra space for '\0'
     std::unique_ptr<char[]> buf(new char[size]);
-    std::snprintf(buf.get(), size, format.c_str(), args...);
+    snprintf(buf.get(), size, format.c_str(), args...);
     return std::string(buf.get(), buf.get() + size - 1); // We don't want the '\0' inside
 }
 
diff --git a/CMakeLists.txt b/CMakeLists.txt
index c3650a05..93ef6ada 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -11,8 +11,8 @@ set(FAMILIES generic ice40)
 set(CMAKE_CXX_STANDARD 11)
 if (MSVC)
 set(CMAKE_CONFIGURATION_TYPES "Debug;Release" CACHE STRING "" FORCE)
-set(CMAKE_CXX_FLAGS_DEBUG "${CMAKE_CXX_FLAGS_DEBUG} /D_DEBUG /W4 /wd4100 /wd4244 /wd4125 /wd4800 /wd4456 /wd4458 /wd4305 /wd4459 /wd4121")
-set(CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS_RELEASE} /W4 /wd4100 /wd4244 /wd4125 /wd4800 /wd4456 /wd4458 /wd4305 /wd4459 /wd4121")
+set(CMAKE_CXX_FLAGS_DEBUG "${CMAKE_CXX_FLAGS_DEBUG} /D_DEBUG /W4 /wd4100 /wd4244 /wd4125 /wd4800 /wd4456 /wd4458 /wd4305 /wd4459 /wd4121 /wd4996")
+set(CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS_RELEASE} /W4 /wd4100 /wd4244 /wd4125 /wd4800 /wd4456 /wd4458 /wd4305 /wd4459 /wd4121 /wd4996")
 else()
 set(CMAKE_CXX_FLAGS_DEBUG "-Wall -fPIC -ggdb")
 set(CMAKE_CXX_FLAGS_RELEASE "-Wall -fPIC -O3 -g")
@@ -21,6 +21,10 @@ set(CMAKE_DEFIN)
 
 set(CMAKE_MODULE_PATH "${CMAKE_SOURCE_DIR}/3rdparty/sanitizers-cmake/cmake" ${CMAKE_MODULE_PATH})
 
+if(NOT DEFINED CMAKE_SUPPRESS_DEVELOPER_WARNINGS)
+     set(CMAKE_SUPPRESS_DEVELOPER_WARNINGS 1 CACHE INTERNAL "No dev warnings")
+endif()
+
 find_package(Sanitizers)
 
 # List of Boost libraries to include
diff --git a/gui/fpgaviewwidget.h b/gui/fpgaviewwidget.h
index 0cd84c9c..0342bb8a 100644
--- a/gui/fpgaviewwidget.h
+++ b/gui/fpgaviewwidget.h
@@ -34,17 +34,17 @@ NEXTPNR_NAMESPACE_BEGIN
 
 // Vertex2DPOD is a structure of X, Y coordinates that can be passed to OpenGL
 // directly.
-struct Vertex2DPOD
+NPNR_PACKED_STRUCT(struct Vertex2DPOD
 {
     GLfloat x;
     GLfloat y;
 
     Vertex2DPOD(GLfloat X, GLfloat Y) : x(X), y(Y) {}
-} __attribute__((packed));
+});
 
 // Vertex2DPOD is a structure of R, G, B, A values that can be passed to OpenGL
 // directly.
-struct ColorPOD
+NPNR_PACKED_STRUCT(struct ColorPOD
 {
     GLfloat r;
     GLfloat g;
@@ -53,7 +53,7 @@ struct ColorPOD
 
     ColorPOD(GLfloat R, GLfloat G, GLfloat B, GLfloat A) : r(R), g(G), b(B), a(A) {}
     ColorPOD(const QColor &color) : r(color.redF()), g(color.greenF()), b(color.blueF()), a(color.alphaF()) {}
-} __attribute__((packed));
+});
 
 // LineShaderData is a built set of vertices that can be rendered by the
 // LineShader.