diff --git a/cmake/platforms/Linux32.cmake b/cmake/platforms/Linux32.cmake
--- a/cmake/platforms/Linux32.cmake
+++ b/cmake/platforms/Linux32.cmake
@@ -1,12 +1,16 @@
 # Copyright (c) 2019 The Bitcoin developers
 
 set(CMAKE_SYSTEM_NAME Linux)
+set(CMAKE_SYSTEM_PROCESSOR i686)
 set(TOOLCHAIN_PREFIX i686-pc-linux-gnu)
 
 # Cross compilers to use for C and C++
 set(CMAKE_C_COMPILER gcc)
 set(CMAKE_CXX_COMPILER g++)
 
+set(CMAKE_C_COMPILER_TARGET ${TOOLCHAIN_PREFIX})
+set(CMAKE_CXX_COMPILER_TARGET ${TOOLCHAIN_PREFIX})
+
 # Target environment on the build host system
 # Set 1st to directory with the cross compiler's C/C++ headers/libs
 set(CMAKE_FIND_ROOT_PATH "${CMAKE_CURRENT_SOURCE_DIR}/depends/${TOOLCHAIN_PREFIX}")
diff --git a/cmake/platforms/Linux64.cmake b/cmake/platforms/Linux64.cmake
--- a/cmake/platforms/Linux64.cmake
+++ b/cmake/platforms/Linux64.cmake
@@ -1,12 +1,16 @@
 # Copyright (c) 2019 The Bitcoin developers
 
 set(CMAKE_SYSTEM_NAME Linux)
+set(CMAKE_SYSTEM_PROCESSOR x86_64)
 set(TOOLCHAIN_PREFIX x86_64-linux-gnu)
 
 # Cross compilers to use for C and C++
 set(CMAKE_C_COMPILER gcc)
 set(CMAKE_CXX_COMPILER g++)
 
+set(CMAKE_C_COMPILER_TARGET ${TOOLCHAIN_PREFIX})
+set(CMAKE_CXX_COMPILER_TARGET ${TOOLCHAIN_PREFIX})
+
 # Target environment on the build host system
 # Set 1st to directory with the cross compiler's C/C++ headers/libs
 set(CMAKE_FIND_ROOT_PATH "${CMAKE_CURRENT_SOURCE_DIR}/depends/${TOOLCHAIN_PREFIX}")
diff --git a/cmake/platforms/LinuxAArch64.cmake b/cmake/platforms/LinuxAArch64.cmake
--- a/cmake/platforms/LinuxAArch64.cmake
+++ b/cmake/platforms/LinuxAArch64.cmake
@@ -1,12 +1,16 @@
 # Copyright (c) 2019 The Bitcoin developers
 
 set(CMAKE_SYSTEM_NAME Linux)
+set(CMAKE_SYSTEM_PROCESSOR aarch64)
 set(TOOLCHAIN_PREFIX aarch64-linux-gnu)
 
 # Cross compilers to use for C and C++
 set(CMAKE_C_COMPILER ${TOOLCHAIN_PREFIX}-gcc)
 set(CMAKE_CXX_COMPILER ${TOOLCHAIN_PREFIX}-g++)
 
+set(CMAKE_C_COMPILER_TARGET ${TOOLCHAIN_PREFIX})
+set(CMAKE_CXX_COMPILER_TARGET ${TOOLCHAIN_PREFIX})
+
 # Target environment on the build host system
 # Set 1st to directory with the cross compiler's C/C++ headers/libs
 set(CMAKE_FIND_ROOT_PATH
diff --git a/cmake/platforms/LinuxARM.cmake b/cmake/platforms/LinuxARM.cmake
--- a/cmake/platforms/LinuxARM.cmake
+++ b/cmake/platforms/LinuxARM.cmake
@@ -1,12 +1,16 @@
 # Copyright (c) 2019 The Bitcoin developers
 
 set(CMAKE_SYSTEM_NAME Linux)
+set(CMAKE_SYSTEM_PROCESSOR arm)
 set(TOOLCHAIN_PREFIX arm-linux-gnueabihf)
 
 # Cross compilers to use for C and C++
 set(CMAKE_C_COMPILER ${TOOLCHAIN_PREFIX}-gcc)
 set(CMAKE_CXX_COMPILER ${TOOLCHAIN_PREFIX}-g++)
 
+set(CMAKE_C_COMPILER_TARGET ${TOOLCHAIN_PREFIX})
+set(CMAKE_CXX_COMPILER_TARGET ${TOOLCHAIN_PREFIX})
+
 # Target environment on the build host system
 # Set 1st to directory with the cross compiler's C/C++ headers/libs
 set(CMAKE_FIND_ROOT_PATH
diff --git a/cmake/platforms/OSX.cmake b/cmake/platforms/OSX.cmake
--- a/cmake/platforms/OSX.cmake
+++ b/cmake/platforms/OSX.cmake
@@ -1,16 +1,21 @@
 # Copyright (c) 2017 The Bitcoin developers
 
 set(CMAKE_SYSTEM_NAME Darwin)
+set(CMAKE_SYSTEM_PROCESSOR x86_64)
 set(TOOLCHAIN_PREFIX x86_64-apple-darwin14)
 
 # On OSX, we use clang by default.
 set(CMAKE_C_COMPILER clang)
 set(CMAKE_CXX_COMPILER clang++)
 
+set(CMAKE_C_COMPILER_TARGET ${TOOLCHAIN_PREFIX})
+set(CMAKE_CXX_COMPILER_TARGET ${TOOLCHAIN_PREFIX})
+
 # On OSX we use various stuff from Apple's SDK.
 set(OSX_SDK_PATH "${CMAKE_CURRENT_SOURCE_DIR}/depends/SDKs/MacOSX10.11.sdk")
 set(CMAKE_OSX_SYSROOT ${OSX_SDK_PATH})
 set(CMAKE_OSX_DEPLOYMENT_TARGET 10.10)
+set(CMAKE_OSX_ARCHITECTURES x86_64)
 
 # target environment on the build host system
 #   set 1st to dir with the cross compiler's C/C++ headers/libs
@@ -28,7 +33,6 @@
 
 # Sysroot clang
 set(OSX_EXTRA_FLAGS
-	" -target ${TOOLCHAIN_PREFIX}"
 	" -mlinker-version=253.9"
 )
 
diff --git a/cmake/platforms/Win32.cmake b/cmake/platforms/Win32.cmake
--- a/cmake/platforms/Win32.cmake
+++ b/cmake/platforms/Win32.cmake
@@ -1,6 +1,7 @@
 # Copyright (c) 2017 The Bitcoin developers
 
 set(CMAKE_SYSTEM_NAME Windows)
+set(CMAKE_SYSTEM_PROCESSOR i686)
 set(TOOLCHAIN_PREFIX i686-w64-mingw32)
 
 # cross compilers to use for C and C++
@@ -8,6 +9,9 @@
 set(CMAKE_CXX_COMPILER ${TOOLCHAIN_PREFIX}-g++)
 set(CMAKE_RC_COMPILER ${TOOLCHAIN_PREFIX}-windres)
 
+set(CMAKE_C_COMPILER_TARGET ${TOOLCHAIN_PREFIX})
+set(CMAKE_CXX_COMPILER_TARGET ${TOOLCHAIN_PREFIX})
+
 # target environment on the build host system
 #   set 1st to dir with the cross compiler's C/C++ headers/libs
 set(CMAKE_FIND_ROOT_PATH "${CMAKE_CURRENT_SOURCE_DIR}/depends/${TOOLCHAIN_PREFIX};/usr/${TOOLCHAIN_PREFIX}")
diff --git a/cmake/platforms/Win64.cmake b/cmake/platforms/Win64.cmake
--- a/cmake/platforms/Win64.cmake
+++ b/cmake/platforms/Win64.cmake
@@ -1,6 +1,7 @@
 # Copyright (c) 2017 The Bitcoin developers
 
 set(CMAKE_SYSTEM_NAME Windows)
+set(CMAKE_SYSTEM_PROCESSOR x86_64)
 set(TOOLCHAIN_PREFIX x86_64-w64-mingw32)
 
 # cross compilers to use for C and C++
@@ -8,6 +9,9 @@
 set(CMAKE_CXX_COMPILER ${TOOLCHAIN_PREFIX}-g++)
 set(CMAKE_RC_COMPILER ${TOOLCHAIN_PREFIX}-windres)
 
+set(CMAKE_C_COMPILER_TARGET ${TOOLCHAIN_PREFIX})
+set(CMAKE_CXX_COMPILER_TARGET ${TOOLCHAIN_PREFIX})
+
 # target environment on the build host system
 #   set 1st to dir with the cross compiler's C/C++ headers/libs
 set(CMAKE_FIND_ROOT_PATH "${CMAKE_CURRENT_SOURCE_DIR}/depends/${TOOLCHAIN_PREFIX};/usr/${TOOLCHAIN_PREFIX}")