Use C++17 for qmake and force the build of everything with C++17

We will want to use C++17 code in our headers soon.
(including the one in the bootstrap libraries)

This patch is quick and dirty, I guess it will be cleaner once we move to cmake

Updated QMAKE_MACOSX_DEPLOYMENT_TARGET because 10.13 runtime does
not support C++17 stdlib features

Change-Id: I75ac171436945dddd1bb953a9c8d323ac20da7ac
Reviewed-by: Lars Knoll <lars.knoll@qt.io>

6 files changed, 13 insertions, 15 deletions

diff --git a/configure b/configure
index 5cd2787bda..34312cbcf8 100755
--- a/configure
+++ b/configure
@@ -831,14 +831,14 @@ fi
         echo "########################################################################" > "$mkfile"
         echo "## This file was autogenerated by configure, all changes will be lost ##" >> "$mkfile"
         echo "########################################################################" >> "$mkfile"
-        EXTRA_CXXFLAGS="\$(QMAKE_CXXFLAGS) \$(QMAKE_CXXFLAGS_CXX11) \$(QMAKE_CXXFLAGS_SPLIT_SECTIONS)"
+        EXTRA_CXXFLAGS="\$(QMAKE_CXXFLAGS) \$(QMAKE_CXXFLAGS_CXX1Z) \$(QMAKE_CXXFLAGS_SPLIT_SECTIONS)"
         EXTRA_LFLAGS="\$(QMAKE_LFLAGS) \$(QMAKE_LFLAGS_GCSECTIONS)"
 
         [ "$CFG_SILENT" = "yes" ] && CC_TRANSFORM='s,^,\@,' || CC_TRANSFORM=
         setBootstrapVariable QMAKE_CC CC "$CC_TRANSFORM"
         setBootstrapVariable QMAKE_CXX CXX "$CC_TRANSFORM"
         setBootstrapVariable QMAKE_CXXFLAGS
-        setBootstrapVariable QMAKE_CXXFLAGS_CXX11
+        setBootstrapVariable QMAKE_CXXFLAGS_CXX1Z
         setBootstrapVariable QMAKE_CXXFLAGS_SPLIT_SECTIONS
         setBootstrapVariable QMAKE_LFLAGS
         setBootstrapVariable QMAKE_LFLAGS_GCSECTIONS
diff --git a/mkspecs/common/icc-base-unix.conf b/mkspecs/common/icc-base-unix.conf
index e0bb55577e..5fba8dbfbb 100644
--- a/mkspecs/common/icc-base-unix.conf
+++ b/mkspecs/common/icc-base-unix.conf
@@ -68,7 +68,7 @@ QMAKE_CXXFLAGS_SPLIT_SECTIONS = $$QMAKE_CFLAGS_SPLIT_SECTIONS
 QMAKE_CXXFLAGS_EXCEPTIONS_OFF = -fno-exceptions
 QMAKE_CXXFLAGS_CXX11    = -std=c++11
 QMAKE_CXXFLAGS_CXX14    = -std=c++1y
-QMAKE_CXXFLAGS_CXX1Z    = -std=c++1z
+QMAKE_CXXFLAGS_CXX1Z    = -std=c++17
 QMAKE_CXXFLAGS_GNUCXX11 = -std=gnu++11
 QMAKE_CXXFLAGS_GNUCXX14 = -std=gnu++1y
 QMAKE_CXXFLAGS_GNUCXX1Z = -std=gnu++1z
diff --git a/mkspecs/common/macx.conf b/mkspecs/common/macx.conf
index d16b77acb8..6a1b076d7d 100644
--- a/mkspecs/common/macx.conf
+++ b/mkspecs/common/macx.conf
@@ -5,7 +5,7 @@
 QMAKE_PLATFORM         += macos osx macx
 QMAKE_MAC_SDK           = macosx
 
-QMAKE_MACOSX_DEPLOYMENT_TARGET = 10.13
+QMAKE_MACOSX_DEPLOYMENT_TARGET = 10.14
 QMAKE_APPLE_DEVICE_ARCHS = x86_64
 
 # Should be 10.15, but as long as the CI builds with
diff --git a/mkspecs/common/qcc-base-qnx.conf b/mkspecs/common/qcc-base-qnx.conf
index 4725371c29..dce6d8ea2c 100644
--- a/mkspecs/common/qcc-base-qnx.conf
+++ b/mkspecs/common/qcc-base-qnx.conf
@@ -46,7 +46,7 @@ QMAKE_RPATHLINKDIR_POST += $${QNX_DIR}/$${QNX_CPUDIR}/lib $${QNX_DIR}/$${QNX_CPU
 
 QMAKE_CXXFLAGS_CXX11    =
 QMAKE_CXXFLAGS_CXX14    =
-QMAKE_CXXFLAGS_CXX1Z    =
+QMAKE_CXXFLAGS_CXX1Z    = -Wc,-std=gnu++1z
 
 QMAKE_CXXFLAGS_GNUCXX11 = -Wc,-std=gnu++11
 QMAKE_CXXFLAGS_GNUCXX14 = -Wc,-std=gnu++1y
diff --git a/mkspecs/features/default_post.prf b/mkspecs/features/default_post.prf
index 1d79f5c958..9c73eeef69 100644
--- a/mkspecs/features/default_post.prf
+++ b/mkspecs/features/default_post.prf
@@ -124,22 +124,20 @@ breakpad {
 c++17: CONFIG += c++1z
 c++latest: CONFIG *= c++2a c++1z c++14 c++11
 
-!c++11:!c++14:!c++1z:!c++2a {
-    # Qt requires C++11 since 5.7, check if we need to force a compiler option
+!c++1z:!c++2a {
+    # Qt requires C++17
     QT_COMPILER_STDCXX_no_L = $$replace(QT_COMPILER_STDCXX, "L$", "")
-    !greaterThan(QT_COMPILER_STDCXX_no_L, 199711): CONFIG += c++11
+    !greaterThan(QT_COMPILER_STDCXX_no_L, 201402): CONFIG += c++1z
 }
-c++11|c++14|c++1z|c++2a {
+c++1z|c++2a {
     # Disable special compiler flags for host builds
     !host_build|!cross_compile {
         c++2a:       cxxstd = CXX2A
-        else: c++1z: cxxstd = CXX1Z
-        else: c++14: cxxstd = CXX14
-        else:        cxxstd = CXX11
+        else:        cxxstd = CXX1Z
     } else {
-        # Fall back to c++11, because since 5.7 c++11 is required everywhere,
+        # Fall back to c++17, because C++17 is required everywhere,
         # including host builds
-        cxxstd = CXX11
+        cxxstd = CXX1Z
     }
 
     # Check if we should disable compiler extensions or not
diff --git a/qmake/Makefile.win32 b/qmake/Makefile.win32
index 6f27b735d4..20644595d2 100644
--- a/qmake/Makefile.win32
+++ b/qmake/Makefile.win32
@@ -28,7 +28,7 @@ CFLAGS_PCH        = -Yuqmake_pch.h -FIqmake_pch.h -Fpqmake_pch.pch
 PCH_OBJECT        = qmake_pch.obj
 
 CFLAGS_BARE = -c -Fo./ -Fdqmake.pdb \
-              -W2 -nologo -O2 \
+              -W2 -nologo -O2 -std:c++17 -Zc:__cplusplus \
               $(CFLAGS_EXTRA) \
               -I$(QMKSRC) -I$(QMKSRC)\library -I$(QMKSRC)\generators -I$(QMKSRC)\generators\unix -I$(QMKSRC)\generators\win32 -I$(QMKSRC)\generators\mac \
               -I$(SOURCE_PATH)/src/3rdparty/tinycbor/src \