From f67afee9e932dd220474227882a745233455d729 Mon Sep 17 00:00:00 2001
From: Oswald Buddenhagen <oswald.buddenhagen@qt.io>
Date: Thu, 12 Jan 2017 20:52:51 +0100
Subject: [PATCH] determine QMAKE_DEFAULT_{INC,LIB}DIRS separately for host and
 target

note that in principle this leaves room for a race condition, as the
first project to determine the host config is not going to be the
top-level one.
in qtbase and qtdeclarative, this is naturally serialized via the common
bootstrapped libraries (bootstrap resp. qmldevtools). activeqt, qt3d,
qtscxml, and qtwayland all build only one bootstrapped tool each.
qtwebengine makes a fake host build to create files for gyp/gn; the
convert_dict tool is declared a host tool, but isn't actually built when
x-building anyway, and even if, it's serialized on the former. qttools
needs explicit serialization, though. no other host builds exist within
qt as of now.

Task-number: QTBUG-58126
Change-Id: I81a02a2d98f2bfe5d6aaa51119d5e7919549f119
Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>
---
 mkspecs/features/toolchain.prf | 21 +++++++++++++--------
 1 file changed, 13 insertions(+), 8 deletions(-)

diff --git a/mkspecs/features/toolchain.prf b/mkspecs/features/toolchain.prf
index fdefd513e3..9e11ab9958 100644
--- a/mkspecs/features/toolchain.prf
+++ b/mkspecs/features/toolchain.prf
@@ -12,7 +12,12 @@ defineReplace(qtMakeExpand) {
     }
 }
 
-isEmpty(QMAKE_DEFAULT_INCDIRS):!host_build {
+host_build: \
+    target_prefix = QMAKE_HOST_CXX
+else: \
+    target_prefix = QMAKE_CXX
+
+isEmpty($${target_prefix}.INCDIRS) {
     #
     # Get default include and library paths from compiler
     #
@@ -44,6 +49,8 @@ isEmpty(QMAKE_DEFAULT_INCDIRS):!host_build {
         }
         QMAKE_DEFAULT_LIBDIRS = $$unique(QMAKE_DEFAULT_LIBDIRS)
     } else: msvc {
+        # This doesn't differentiate between host and target,
+        # but neither do the compilers.
         LIB = $$getenv("LIB")
         QMAKE_DEFAULT_LIBDIRS = $$split(LIB, $$QMAKE_DIRLIST_SEP)
         INCLUDE = $$getenv("INCLUDE")
@@ -55,8 +62,11 @@ isEmpty(QMAKE_DEFAULT_INCDIRS):!host_build {
         isEmpty(QMAKE_DEFAULT_LIBDIRS): QMAKE_DEFAULT_LIBDIRS = /lib /usr/lib
     }
 
-    !isEmpty(QMAKE_DEFAULT_INCDIRS): cache(QMAKE_DEFAULT_INCDIRS, set stash)
-    !isEmpty(QMAKE_DEFAULT_LIBDIRS): cache(QMAKE_DEFAULT_LIBDIRS, set stash)
+    cache($${target_prefix}.INCDIRS, set stash, QMAKE_DEFAULT_INCDIRS)
+    cache($${target_prefix}.LIBDIRS, set stash, QMAKE_DEFAULT_LIBDIRS)
+} else {
+    QMAKE_DEFAULT_INCDIRS = $$eval($${target_prefix}.INCDIRS)
+    QMAKE_DEFAULT_LIBDIRS = $$eval($${target_prefix}.LIBDIRS)
 }
 
 #
@@ -73,11 +83,6 @@ defineReplace(qtVariablesFromGCC) {
     return($$system("$$1 -E $$system_quote($$PWD/data/macros.cpp) <$$null_device 2>$$null_device", lines))
 }
 
-host_build: \
-    target_prefix = QMAKE_HOST_CXX
-else: \
-    target_prefix = QMAKE_CXX
-
 isEmpty($${target_prefix}.COMPILER_MACROS) {
     msvc {
         clang_cl {