Move pointer size detection entirely to qprocessordetection.h

This commit removes the legacy ptrsize check, which was deficient
because it did not work for multiarch systems (when we supported fat
OS X binaries) and did not work for bootstrap builds because the size
might be different when cross-compiling.

Instead, let's rely on the predefined preprocessor macros to detect
correctly. As a nice side-effect, this fixes 64-bit Android builds
cross-compiled from Windows.

Task-number: QTBUG-48932
Change-Id: I1d0f78915b5942aab07cffff140f9a52b9342f23
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@theqtcompany.com>
Reviewed-by: Erik Verbruggen <erik.verbruggen@theqtcompany.com>

3 files changed, 28 insertions, 23 deletions

diff --git a/src/corelib/global/qglobal.cpp b/src/corelib/global/qglobal.cpp
index 02220d0db2..ed8a9163d4 100644
--- a/src/corelib/global/qglobal.cpp
+++ b/src/corelib/global/qglobal.cpp
@@ -120,9 +120,7 @@ Q_CORE_EXPORT void *qMemSet(void *dest, int c, size_t n);
 // (if this list becomes too long, consider factoring into a separate file)
 Q_STATIC_ASSERT_X(sizeof(int) == 4, "Qt assumes that int is 32 bits");
 Q_STATIC_ASSERT_X(UCHAR_MAX == 255, "Qt assumes that char is 8 bits");
-#ifndef QT_BOOTSTRAPPED
-Q_STATIC_ASSERT_X(QT_POINTER_SIZE == sizeof(void *), "configure test ptrsize failed to correctly determine QT_POINTER_SIZE");
-#endif
+Q_STATIC_ASSERT_X(QT_POINTER_SIZE == sizeof(void *), "QT_POINTER_SIZE defined incorrectly");
 
 /*!
     \class QFlag
diff --git a/src/corelib/global/qglobal.h b/src/corelib/global/qglobal.h
index d86e410194..db8c60831f 100644
--- a/src/corelib/global/qglobal.h
+++ b/src/corelib/global/qglobal.h
@@ -193,18 +193,6 @@ typedef unsigned long long quint64; /* 64 bit unsigned */
 typedef qint64 qlonglong;
 typedef quint64 qulonglong;
 
-#ifndef QT_POINTER_SIZE
-#  if defined(Q_OS_WIN64) || (defined(Q_OS_WINRT) && defined(_M_X64))
-#   define QT_POINTER_SIZE 8
-#  elif defined(Q_OS_WIN32) || defined(Q_OS_WINCE) || defined(Q_OS_WINRT)
-#   define QT_POINTER_SIZE 4
-#  elif defined(Q_OS_ANDROID)
-#   define QT_POINTER_SIZE 4 // ### Add auto-detection to Windows configure
-#  elif !defined(QT_BOOTSTRAPPED)
-#   error could not determine QT_POINTER_SIZE
-#  endif
-#endif
-
 /*
    Useful type definitions for Qt
 */
diff --git a/src/corelib/global/qprocessordetection.h b/src/corelib/global/qprocessordetection.h
index a026224021..4b75872bb6 100644
--- a/src/corelib/global/qprocessordetection.h
+++ b/src/corelib/global/qprocessordetection.h
@@ -91,6 +91,7 @@
 #  define Q_PROCESSOR_ARM
 #  if defined(__aarch64__)
 #    define Q_PROCESSOR_ARM_64
+#    define Q_PROCESSOR_WORDSIZE 8
 #  else
 #    define Q_PROCESSOR_ARM_32
 #  endif
@@ -228,6 +229,7 @@
 #  endif
 #  if defined(_MIPS_ARCH_MIPS64) || defined(__mips64)
 #    define Q_PROCESSOR_MIPS_64
+#    define Q_PROCESSOR_WORDSIZE 8
 #  endif
 #  if defined(__MIPSEL__)
 #    define Q_BYTE_ORDER Q_LITTLE_ENDIAN
@@ -252,6 +254,7 @@
 #  define Q_PROCESSOR_POWER
 #  if defined(__ppc64__) || defined(__powerpc64__) || defined(__64BIT__)
 #    define Q_PROCESSOR_POWER_64
+#    define Q_PROCESSOR_WORDSIZE 8
 #  else
 #    define Q_PROCESSOR_POWER_32
 #  endif
@@ -323,6 +326,28 @@
 #endif
 
 /*
+   Size of a pointer and the machine register size. We detect a 64-bit system by:
+   * GCC and compatible compilers (Clang, ICC on OS X and Windows) always define
+     __SIZEOF_POINTER__. This catches all known cases of ILP32 builds on 64-bit
+     processors.
+   * Most other Unix compilers define __LP64__ or _LP64 on 64-bit mode
+     (Long and Pointer 64-bit)
+   * If Q_PROCESSOR_WORDSIZE was defined above, it's assumed to match the pointer
+     size.
+   Otherwise, we assume to be 32-bit and then check in qglobal.cpp that it is right.
+*/
+
+#if defined __SIZEOF_POINTER__
+#  define QT_POINTER_SIZE           __SIZEOF_POINTER__
+#elif defined(__LP64__) || defined(_LP64)
+#  define QT_POINTER_SIZE           8
+#elif defined(Q_PROCESSOR_WORDSIZE)
+#  define QT_POINTER_SIZE           Q_PROCESSOR_WORDSIZE
+#else
+#  define QT_POINTER_SIZE           4
+#endif
+
+/*
    Define Q_PROCESSOR_WORDSIZE to be the size of the machine's word (usually,
    the size of the register). On some architectures where a pointer could be
    smaller than the register, the macro is defined above.
@@ -330,14 +355,8 @@
    Falls back to QT_POINTER_SIZE if not set explicitly for the platform.
 */
 #ifndef Q_PROCESSOR_WORDSIZE
-#  ifdef __SIZEOF_POINTER__
-     /* GCC & friends define this */
-#    define Q_PROCESSOR_WORDSIZE        __SIZEOF_POINTER__
-#  elif defined(_LP64) || defined(__LP64__) || defined(WIN64) || defined(_WIN64)
-#    define Q_PROCESSOR_WORDSIZE        8
-#  else
-#    define Q_PROCESSOR_WORDSIZE        QT_POINTER_SIZE
-#  endif
+#  define Q_PROCESSOR_WORDSIZE        QT_POINTER_SIZE
 #endif
 
+
 #endif // QPROCESSORDETECTION_H