cmake: make static flags configurable

Author: tobtoht

CMakeLists.txt

@@ -995,9 +995,10 @@ include(CheckTrezor)
   set(CMAKE_C_FLAGS_RELEASE "${CMAKE_C_FLAGS_RELEASE} ${RELEASE_FLAGS}")
   set(CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS_RELEASE} ${RELEASE_FLAGS}")
 
-  if(STATIC)
-    # STATIC already configures most deps to be linked in statically,
-    # here we make more deps static if the platform permits it
+if(STATIC)
+  # STATIC already configures most deps to be linked in statically,
+  # here we make more deps static if the platform permits it
+  if (NOT DEFINED STATIC_FLAGS)
     if (MINGW)
       # On Windows, this is as close to fully-static as we get:
       # this leaves only deps on /c/Windows/system32/*.dll
@@ -1006,8 +1007,9 @@ include(CheckTrezor)
       # On Linux, we don't support fully static build, but these can be static
       set(STATIC_FLAGS "-static-libgcc -static-libstdc++")
     endif()
-    set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} ${STATIC_FLAGS} ")
   endif()
+  set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} ${STATIC_FLAGS} ")
+endif()
 
 set(OLD_LIB_SUFFIXES ${CMAKE_FIND_LIBRARY_SUFFIXES})
 set(Boost_NO_BOOST_CMAKE ON)