diff --git a/config.tests/common/avx/avx.pro b/config.tests/common/avx/avx.pro
index 8d1b9702bcc..bf84089883e 100644
--- a/config.tests/common/avx/avx.pro
+++ b/config.tests/common/avx/avx.pro
@@ -1,5 +1,5 @@
 SOURCES = avx.cpp
 CONFIG -= qt dylib release debug_and_release
 CONFIG += debug console
-isEmpty(QMAKE_CFLAGS_AVX):error("This compiler does not support AVX")
+!defined(QMAKE_CFLAGS_AVX, "var"):error("This compiler does not support AVX")
 else:QMAKE_CXXFLAGS += $$QMAKE_CFLAGS_AVX
diff --git a/config.tests/common/avx2/avx2.pro b/config.tests/common/avx2/avx2.pro
index 927f64efc8c..7ccf66ca28b 100644
--- a/config.tests/common/avx2/avx2.pro
+++ b/config.tests/common/avx2/avx2.pro
@@ -1,5 +1,5 @@
 SOURCES = avx2.cpp
 CONFIG -= qt dylib release debug_and_release
 CONFIG += debug console
-isEmpty(QMAKE_CFLAGS_AVX2):error("This compiler does not support AVX2")
+!defined(QMAKE_CFLAGS_AVX2, "var"):error("This compiler does not support AVX2")
 else:QMAKE_CXXFLAGS += $$QMAKE_CFLAGS_AVX2
diff --git a/config.tests/common/avx512/avx512.pro b/config.tests/common/avx512/avx512.pro
index 37cfb2ea541..96dddb14fd6 100644
--- a/config.tests/common/avx512/avx512.pro
+++ b/config.tests/common/avx512/avx512.pro
@@ -2,11 +2,11 @@ SOURCES = avx512.cpp
 CONFIG -= qt dylib release debug_and_release
 CONFIG += debug console
 
-isEmpty(AVX512): error("You must set the AVX512 variable!")
+!defined(AVX512, "var"): error("You must set the AVX512 variable!")
 
 varname = QMAKE_CFLAGS_AVX512$$AVX512
 value = $$eval($$varname)
-isEmpty($$varname): error("This compiler does not support AVX512")
+!defined($$varname, "var"): error("This compiler does not support AVX512")
 
 QMAKE_CXXFLAGS += $$value
 DEFINES += AVX512WANT=$$AVX512
diff --git a/config.tests/common/sse2/sse2.pro b/config.tests/common/sse2/sse2.pro
index b4031f13fa4..0567eba19d0 100644
--- a/config.tests/common/sse2/sse2.pro
+++ b/config.tests/common/sse2/sse2.pro
@@ -1,5 +1,5 @@
 SOURCES = sse2.cpp
 CONFIG -= qt dylib release debug_and_release
 CONFIG += debug console
-isEmpty(QMAKE_CFLAGS_SSE2):error("This compiler does not support SSE2")
+!defined(QMAKE_CFLAGS_SSE2, var): error("This compiler does not support SSE2")
 else:QMAKE_CXXFLAGS += $$QMAKE_CFLAGS_SSE2
diff --git a/config.tests/common/sse3/sse3.pro b/config.tests/common/sse3/sse3.pro
index f704c40c759..e2e09bac91d 100644
--- a/config.tests/common/sse3/sse3.pro
+++ b/config.tests/common/sse3/sse3.pro
@@ -1,5 +1,5 @@
 SOURCES = sse3.cpp
 CONFIG -= qt dylib release debug_and_release
 CONFIG += debug console
-isEmpty(QMAKE_CFLAGS_SSE3):error("This compiler does not support SSE3")
+!defined(QMAKE_CFLAGS_SSE3, "var"):error("This compiler does not support SSE3")
 else:QMAKE_CXXFLAGS += $$QMAKE_CFLAGS_SSE3
diff --git a/config.tests/common/sse4_1/sse4_1.pro b/config.tests/common/sse4_1/sse4_1.pro
index 5cc04e7c5cf..273c705efc1 100644
--- a/config.tests/common/sse4_1/sse4_1.pro
+++ b/config.tests/common/sse4_1/sse4_1.pro
@@ -1,5 +1,5 @@
 SOURCES = sse4_1.cpp
 CONFIG -= qt dylib release debug_and_release
 CONFIG += debug console
-isEmpty(QMAKE_CFLAGS_SSE4_1):error("This compiler does not support SSE4.1")
+!defined(QMAKE_CFLAGS_SSE4_1, "var"):error("This compiler does not support SSE4.1")
 else:QMAKE_CXXFLAGS += $$QMAKE_CFLAGS_SSE4_1
diff --git a/config.tests/common/sse4_2/sse4_2.pro b/config.tests/common/sse4_2/sse4_2.pro
index 6a04b1f9a59..3816fdeae97 100644
--- a/config.tests/common/sse4_2/sse4_2.pro
+++ b/config.tests/common/sse4_2/sse4_2.pro
@@ -1,5 +1,5 @@
 SOURCES = sse4_2.cpp
 CONFIG -= qt dylib release debug_and_release
 CONFIG += debug console
-isEmpty(QMAKE_CFLAGS_SSE4_2):error("This compiler does not support SSE4.2")
+!defined(QMAKE_CFLAGS_SSE4_2, "var"):error("This compiler does not support SSE4.2")
 else:QMAKE_CXXFLAGS += $$QMAKE_CFLAGS_SSE4_2
diff --git a/config.tests/common/ssse3/ssse3.pro b/config.tests/common/ssse3/ssse3.pro
index 5b207e78ce1..597b1691402 100644
--- a/config.tests/common/ssse3/ssse3.pro
+++ b/config.tests/common/ssse3/ssse3.pro
@@ -1,5 +1,5 @@
 SOURCES = ssse3.cpp
 CONFIG -= qt dylib release debug_and_release
 CONFIG += debug console
-isEmpty(QMAKE_CFLAGS_SSSE3):error("This compiler does not support SSSE3")
+!defined(QMAKE_CFLAGS_SSSE3, "var"):error("This compiler does not support SSSE3")
 else:QMAKE_CXXFLAGS += $$QMAKE_CFLAGS_SSSE3
diff --git a/mkspecs/common/msvc-desktop.conf b/mkspecs/common/msvc-desktop.conf
index eec9e1f688a..1b9d57bff05 100644
--- a/mkspecs/common/msvc-desktop.conf
+++ b/mkspecs/common/msvc-desktop.conf
@@ -35,11 +35,18 @@ QMAKE_CFLAGS_RELEASE_WITH_DEBUGINFO += -O2 -MD -Zi
 QMAKE_CFLAGS_DEBUG      = -Zi -MDd
 QMAKE_CFLAGS_YACC       =
 QMAKE_CFLAGS_LTCG       = -GL
-QMAKE_CFLAGS_SSE2       = -arch:SSE2
-QMAKE_CFLAGS_SSE3       = -arch:SSE2
-QMAKE_CFLAGS_SSSE3      = -arch:SSE2
-QMAKE_CFLAGS_SSE4_1     = -arch:SSE2
-QMAKE_CFLAGS_SSE4_2     = -arch:SSE2
+
+contains(QMAKE_TARGET.arch, x86_64) {
+    # SSE2 is mandatory on 64-bit mode, so skip the option. It triggers:
+    # cl : Command line warning D9002 : ignoring unknown option '-arch:SSE2'
+    QMAKE_CFLAGS_SSE2   =
+} else {
+    QMAKE_CFLAGS_SSE2   = -arch:SSE2
+}
+QMAKE_CFLAGS_SSE3       = $$QMAKE_CFLAGS_SSE2
+QMAKE_CFLAGS_SSSE3      = $$QMAKE_CFLAGS_SSE2
+QMAKE_CFLAGS_SSE4_1     = $$QMAKE_CFLAGS_SSE2
+QMAKE_CFLAGS_SSE4_2     = $$QMAKE_CFLAGS_SSE2
 
 QMAKE_CXX               = $$QMAKE_CC
 QMAKE_CXXFLAGS          = $$QMAKE_CFLAGS