Improve the architecture-detection mechanism

For the Unix part, this now obeys the -v option, printing the full
command-line it used to compile, allowing testers to identify why
something went wrong.

Unfortunately, it requires a full compilation cycle, instead of just
preprocessing. Just one more among the many on Unix, but maybe a
noticeable slow-down on Windows.

Change-Id: I654b70d99887e04c96731a5b91be9ad555e4d8fe
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@nokia.com>
Reviewed-by: Girish Ramakrishnan <girish.1.ramakrishnan@nokia.com>

config.tests/arch/arch.cpp

@@ -1,6 +1,7 @@
 /****************************************************************************
 **
 ** Copyright (C) 2012 Nokia Corporation and/or its subsidiary(-ies).
+** Copyright (C) 2012 Intel Corporation
 ** Contact: http://www.qt-project.org/
 **
 ** This file is part of the FOO module of the Qt Toolkit.
@@ -39,46 +40,43 @@
 **
 ****************************************************************************/
 
-// NOTE: This file is not meant to be compiled, only preprocessed.
 #define QGLOBAL_H
 #include "../../src/corelib/global/qprocessordetection.h"
-#undef alpha
-#undef arm
-#undef avr32
-#undef bfin
-#undef i386
-#undef x86_64
-#undef ia64
-#undef mips
-#undef power
-#undef s390
-#undef sh
-#undef sparc
-#undef unknown
+#include <stdio.h>
+
+extern const char msg[];
+const char msg[] = "==Qt=magic=Qt== Architecture:"
+
 #if defined(Q_PROCESSOR_ALPHA)
-Architecture: alpha
+"alpha"
 #elif defined(Q_PROCESSOR_ARM)
-Architecture: arm
+"arm"
 #elif defined(Q_PROCESSOR_AVR32)
-Architecture: avr32
+"avr32"
 #elif defined(Q_PROCESSOR_BLACKFIN)
-Architecture: bfin
+"bfin"
 #elif defined(Q_PROCESSOR_X86_32)
-Architecture: i386
+"i386"
 #elif defined(Q_PROCESSOR_X86_64)
-Architecture: x86_64
+"x86_64"
 #elif defined(Q_PROCESSOR_IA64)
-Architecture: ia64
+"ia64"
 #elif defined(Q_PROCESSOR_MIPS)
-Architecture: mips
+"mips"
 #elif defined(Q_PROCESSOR_POWER)
-Architecture: power
+"power"
 #elif defined(Q_PROCESSOR_S390)
-Architecture: s390
+"s390"
 #elif defined(Q_PROCESSOR_SH)
-Architecture: sh
+"sh"
 #elif defined(Q_PROCESSOR_SPARC)
-Architecture: sparc
+"sparc"
 #else
-Architecture: unknown
+"unknown"
 #endif
+                   ;
+
+int main()
+{
+    puts(msg);
+}

config.tests/arch/arch.pro

@@ -1,7 +1,4 @@
-CONFIG -= qt debug_and_release
-# Detect target by preprocessing a file that uses Q_PROCESSOR_* macros from qprocessordetection.h
-COMMAND = $$QMAKE_CXX $$QMAKE_CXXFLAGS -E $$PWD/arch.cpp
-# system function converts newline in output into spaces
-COMPILER_ARCH = $$system($$COMMAND)
-# Message back to configure so that it can set QT_ARCH and QT_HOST_ARCH
-message($$COMPILER_ARCH)
+SOURCES = arch.cpp
+CONFIG -= qt dylib release debug_and_release
+CONFIG += debug console
+mac:CONFIG -= app_bundle

config.tests/unix/arch.test

@@ -0,0 +1,41 @@
+#!/bin/sh
+
+QMKSPEC=$1
+VERBOSE=$2
+SRCDIR=$3
+OUTDIR=$4
+RESULTFILE=$5
+
+# debuggery
+[ "$VERBOSE" = "yes" ] && echo "Determining architecture... ($*)"
+
+# build a test program but don't run it
+test -d "$OUTDIR/config.tests/arch" || mkdir -p "$OUTDIR/config.tests/arch"
+[ -f Makefile ] && $MAKE distclean >/dev/null 2>&1
+"$OUTDIR/bin/qmake" -nocache -spec "$QMKSPEC" "QT_BUILD_TREE=$OUTDIR" "LIBS+=$SYSROOT_FLAG" "QMAKE_CXXFLAGS+=$SYSROOT_FLAG" "$SRCDIR/config.tests/arch/arch.pro" -o "$OUTDIR/config.tests/arch/Makefile" >/dev/null 2>&1 || echo "qmake is broken" >&2
+cd "$OUTDIR/config.tests/arch"
+
+
+ARCH=""
+[ "$VERBOSE" = "yes" ] && $MAKE || $MAKE >/dev/null 2>&1
+
+if [ -f ./arch.exe ]; then
+    binary=./arch.exe
+elif [ -f ./arch ]; then
+    binary=./arch
+else
+    [ "$VERBOSE" = "yes" ] && echo "Unable to determine architecture!"
+    exit 2
+fi
+
+ARCH=`strings - $binary 2>/dev/null | awk -F: '/==Qt=magic=Qt==/ { print $2 }'` ||
+{
+    [ "$VERBOSE" = "yes" ] && echo "Unable to determine architecture!"
+    exit 2
+}
+
+$MAKE distclean >/dev/null 2>&1
+
+[ "$VERBOSE" = "yes" ] && echo "    Found '$ARCH' in binary"
+
+echo "$ARCH" > $5

configure

@@ -3667,17 +3667,35 @@ fi
 #-------------------------------------------------------------------------------
 
 # Use config.tests/arch/arch.pro to has the compiler tell us what the target architecture is
-CFG_ARCH=`OUTDIR="$outpath" "$outpath/bin/qmake" -spec "$XQMAKESPEC" -o /dev/null "$relpath/config.tests/arch/arch.pro" 2>&1 | sed -n -e 's,^Project MESSAGE:.*Architecture: \([a-zA-Z0-9_]*\).*,\1,p'`
-
+OUTFILE=$outpath/arch.result
+"$unixtests/arch.test" "$XQMAKESPEC" $OPT_VERBOSE "$relpath" "$outpath" "$OUTFILE"
+if [ $? -eq 0 ]; then
+    CFG_ARCH=`cat "$OUTFILE"`
+else
+    echo
+    echo "Could not determine the target architecture!"
+    echo "Turn on verbose messaging (-v) to see the final report."
+fi
+rm -f "$OUTFILE" 2>/dev/null
 [ -z "$CFG_ARCH" ] && CFG_ARCH="unknown"
+
 if [ "$QMAKESPEC" != "$XQMAKESPEC" ]; then
     # Do the same test again, using the host compiler
-    CFG_HOST_ARCH=`OUTDIR="$outpath" "$outpath/bin/qmake" -spec "$QMAKESPEC" -o /dev/null "$relpath/config.tests/arch/arch.pro" 2>&1 | sed -n -e 's,^Project MESSAGE:.*Architecture: \([a-zA-Z0-9_]*\).*,\1,p'`
+    SYSROOT_FLAG= "$unixtests/arch.test" "$QMAKESPEC" $OPT_VERBOSE "$relpath" "$outpath" "$OUTFILE"
+    if [ $? -eq 0 ]; then
+        CFG_HOST_ARCH=`cat "$OUTFILE"`
+    else
+        echo
+        echo "Could not determine the host architecture!"
+        echo "Turn on verbose messaging (-v) to see the final report."
+    fi
+    rm -f "$OUTFILE" 2>/dev/null
     [ -z "$CFG_HOST_ARCH" ] && CFG_HOST_ARCH="unknown"
 else
     # not cross compiling, host == target
     CFG_HOST_ARCH="$CFG_ARCH"
 fi
+unset OUTFILE
 
 if [ "$OPT_VERBOSE" = "yes" ]; then
     echo "System architecture: '$CFG_ARCH'"

tools/configure/configureapp.cpp

@@ -2561,16 +2561,47 @@ void Configure::detectArch()
         QString qmakespec = dictionary.value(pair.first);
         QString key = pair.second;
 
+        // run qmake
         QString command =
-                fixSeparators(QString("%1/bin/qmake.exe -spec %2 %3/config.tests/arch/arch.pro -o %4/Makefile.unused 2>&1")
-                              .arg(buildPath, qmakespec, sourcePath, newpwd));
-        QString output = Environment::execute(command);
-        if (output.isEmpty())
-            continue;
+                fixSeparators(QString("%1/bin/qmake.exe -spec %2 %3/config.tests/arch/arch.pro 2>&1")
+                              .arg(buildPath, qmakespec, sourcePath));
+        Environment::execute(command);
 
-        QRegExp re("Project MESSAGE:.*Architecture: ([a-zA-Z0-9_]*)");
-        if (re.indexIn(output) != -1)
-            dictionary[key] = re.cap(1);
+        // compile
+        command = dictionary[ "MAKE" ];
+        if (command.contains("nmake"))
+            command += " /NOLOGO";
+        command += " -s";
+        Environment::execute(command);
+
+        // find the executable that was generated
+        QFile exe("arch.exe");
+        if (!exe.open(QFile::ReadOnly)) { // no Text, this is binary
+            cout << "Could not find output file: " << qPrintable(exe.errorString()) << endl;
+            dictionary["DONE"] = "error";
+            return;
+        }
+        QByteArray exeContents = exe.readAll();
+        exe.close();
+
+        static const char magic[] = "==Qt=magic=Qt== Architecture:";
+        int magicPos = exeContents.indexOf(magic);
+        if (magicPos == -1) {
+            cout << "Internal error, could not find the architecture of the executable" << endl;
+            dictionary["DONE"] = "error";
+            return;
+        }
+        //cout << "Found magic at offset 0x" << hex << magicPos << endl;
+
+        // the conversion from QByteArray will stop at the ending NUL anyway
+        QString arch = QString::fromLatin1(exeContents.constData() + magicPos
+                                           + sizeof(magic) - 1);
+        dictionary[key] = arch;
+
+        //cout << "Detected arch '" << qPrintable(arch) << "'\n";
+
+        // clean up
+        Environment::execute(command + " distclean");
     }
 
     if (!dictionary.contains("QT_HOST_ARCH"))