Add support for using -isystem in qmake

This commit will make qmake use -isystem automatically for any
compilers that declare support for it for any paths that are listed in
QMAKE_DEFAULT_INCDIRS.

Change-Id: I36fefc6d5bba61671f65669f0ea42704b3c3cf31
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@digia.com>

mkspecs/common/clang.conf

@@ -13,6 +13,7 @@ QMAKE_LINK_SHLIB        = $$QMAKE_CXX
 CONFIG                 += clang_pch_style
 QMAKE_PCH_OUTPUT_EXT    = .pch
 
+QMAKE_CFLAGS_ISYSTEM             = -isystem
 QMAKE_CFLAGS_PRECOMPILE          = -x c-header -c ${QMAKE_PCH_INPUT} -o ${QMAKE_PCH_OUTPUT}
 QMAKE_CFLAGS_USE_PRECOMPILE      = -Xclang -include-pch -Xclang ${QMAKE_PCH_OUTPUT}
 QMAKE_CXXFLAGS_PRECOMPILE        = -x c++-header -c ${QMAKE_PCH_INPUT} -o ${QMAKE_PCH_OUTPUT}

mkspecs/common/gcc-base.conf

@@ -40,6 +40,7 @@ QMAKE_CFLAGS_DEBUG         += -g
 QMAKE_CFLAGS_SHLIB         += -fPIC
 QMAKE_CFLAGS_STATIC_LIB    += -fPIC
 QMAKE_CFLAGS_APP           += -fPIE
+QMAKE_CFLAGS_ISYSTEM        = -isystem
 QMAKE_CFLAGS_YACC          += -Wno-unused -Wno-parentheses
 QMAKE_CFLAGS_HIDESYMS      += -fvisibility=hidden
 QMAKE_CFLAGS_EXCEPTIONS_OFF += -fno-exceptions

mkspecs/features/moc.prf

@@ -45,7 +45,8 @@ defineReplace(mocCmdBase) {
         }
         incvar = @$$WIN_INCLUDETEMP
     } else {
-        incvar = $(INCPATH)
+        incvar = -I$$QMAKESPEC -I$$_PRO_FILE_PWD_ $$join(INCLUDEPATH, " -I", -I)
+        incvar += $$QMAKE_FRAMEWORKPATH_FLAGS
     }
     RET += $$QMAKE_MOC $(DEFINES) $$join(QMAKE_COMPILER_DEFINES, " -D", -D) $$incvar $$join(QMAKE_DEFAULT_INCDIRS, " -I", -I) $$QMAKE_MOC_OPTIONS
     return($$RET)

mkspecs/linux-icc/qmake.conf

@@ -22,6 +22,7 @@ QMAKE_CFLAGS_DEBUG      = -O0 -g
 QMAKE_CFLAGS_SHLIB      = -fPIC -fno-jump-tables
 QMAKE_CFLAGS_STATIC_LIB = $$QMAKE_CFLAGS_SHLIB
 QMAKE_CFLAGS_YACC       =
+QMAKE_CFLAGS_ISYSTEM    = -isystem
 QMAKE_CFLAGS_THREAD     = -D_REENTRANT
 
 QMAKE_CFLAGS_SSE2      += -xSSE2

qmake/generators/makefile.cpp

@@ -456,6 +456,8 @@ MakefileGenerator::init()
     if (v["QMAKE_LINK_O_FLAG"].isEmpty())
         v["QMAKE_LINK_O_FLAG"].append("-o ");
 
+    setSystemIncludes(v["QMAKE_DEFAULT_INCDIRS"]);
+
     ProStringList &quc = v["QMAKE_EXTRA_COMPILERS"];
 
     //make sure the COMPILERS are in the correct input/output chain order

qmake/generators/makefiledeps.cpp

@@ -345,6 +345,30 @@ bool QMakeSourceFileInfo::containsSourceFile(const QString &f, SourceFileType ty
     return false;
 }
 
+bool QMakeSourceFileInfo::isSystemInclude(const QString &name)
+{
+    if (QDir::isRelativePath(name)) {
+        // if we got a relative path here, it's either an -I flag with a relative path
+        // or an include file we couldn't locate. Either way, conclude it's not
+        // a system include.
+        return false;
+    }
+
+    for (int i = 0; i < systemIncludes.size(); ++i) {
+        // check if name is located inside the system include dir:
+        QDir systemDir(systemIncludes.at(i));
+        QString relativePath = systemDir.relativeFilePath(name);
+
+        // the relative path might be absolute if we're crossing drives on Windows
+        if (QDir::isAbsolutePath(relativePath) || relativePath.startsWith("../"))
+            continue;
+        debug_msg(5, "File/dir %s is in system dir %s, skipping",
+                  qPrintable(name), qPrintable(systemIncludes.at(i)));
+        return true;
+    }
+    return false;
+}
+
 char *QMakeSourceFileInfo::getBuffer(int s) {
     if(!spare_buffer || spare_buffer_size < s)
         spare_buffer = (char *)realloc(spare_buffer, spare_buffer_size=s);

qmake/generators/makefiledeps.h

@@ -78,6 +78,7 @@ private:
     SourceFiles *files, *includes;
     bool files_changed;
     QList<QMakeLocalFileName> depdirs;
+    QStringList systemIncludes;
 
     //sleezy buffer code
     char *spare_buffer;
@@ -98,6 +99,7 @@ protected:
     virtual QFileInfo findFileInfo(const QMakeLocalFileName &);
 
 public:
+
     QMakeSourceFileInfo(const QString &cachefile="");
     virtual ~QMakeSourceFileInfo();
 
@@ -108,11 +110,15 @@ public:
     inline void setDependencyMode(DependencyMode mode) { dep_mode = mode; }
     inline DependencyMode dependencyMode() const { return dep_mode; }
 
+    void setSystemIncludes(const ProStringList &list)
+    { systemIncludes = list.toQStringList(); }
+
     enum SourceFileType { TYPE_UNKNOWN, TYPE_C, TYPE_UI, TYPE_QRC };
     enum SourceFileSeek { SEEK_DEPS=0x01, SEEK_MOCS=0x02 };
     void addSourceFiles(const ProStringList &, uchar seek, SourceFileType type=TYPE_C);
     void addSourceFile(const QString &, uchar seek, SourceFileType type=TYPE_C);
     bool containsSourceFile(const QString &, SourceFileType type=TYPE_C);
+    bool isSystemInclude(const QString &);
 
     int included(const QString &file);
     QStringList dependencies(const QString &file);

qmake/generators/unix/unixmake2.cpp

@@ -125,10 +125,16 @@ UnixMakefileGenerator::writeMakeParts(QTextStream &t)
         t << " -I" << pwd;
     }
     {
+        QString isystem = var("QMAKE_CFLAGS_ISYSTEM");
         const ProStringList &incs = project->values("INCLUDEPATH");
         for(int i = 0; i < incs.size(); ++i) {
             ProString inc = escapeFilePath(incs.at(i));
-            if(!inc.isEmpty())
+            if (inc.isEmpty())
+                continue;
+
+            if (!isystem.isEmpty() && isSystemInclude(inc.toQString()))
+                t << ' ' << isystem << ' ' << inc;
+            else
                 t << " -I" << inc;
         }
     }

qmake/generators/win32/mingw_make.cpp

@@ -321,12 +321,18 @@ void MingwMakefileGenerator::writeIncPart(QTextStream &t)
         t << "-I" << pwd << " ";
     }
 
+    QString isystem = var("QMAKE_CFLAGS_ISYSTEM");
     const ProStringList &incs = project->values("INCLUDEPATH");
     for (ProStringList::ConstIterator incit = incs.begin(); incit != incs.end(); ++incit) {
         QString inc = (*incit).toQString();
         inc.replace(QRegExp("\\\\$"), "");
         inc.replace(QRegExp("\""), "");
-        t << "-I" << quote << inc << quote << " ";
+
+        if (!isystem.isEmpty() && isSystemInclude(inc))
+            t << isystem << ' ';
+        else
+            t << "-I";
+        t << quote << inc << quote << " ";
     }
     t << "-I" << quote << specdir() << quote
       << endl;