qmake: Add object_parallel_to_source config option

This solves the problem of two source files in the same project
having the same name, which ends up with colliding object files.
It also solves issues with moving files around in the source tree
when the GNUmake option is used together with gcc_MD_depends,
where the dependency file would end up with a dependency to the
old source location.

We already have object_with_source option, but that does not play
nicely with shadow-builds. The new option tries to keep the same
hirarcy in the output dir (while still respecting OBJECTS_DIR),
as the sources. Any source with a path outside of the root project
directory (absolute or relative, ../../foo.cpp), will be put inside
the objects directory with the full path appended.

Change-Id: I0c96291974f4801f4c55a26485d512b15c144c00
Reviewed-by: Marius Storm-Olsen <marius.storm-olsen@nokia.com>

1 files changed, 23 insertions, 0 deletions

diff --git a/qmake/generators/makefile.cpp b/qmake/generators/makefile.cpp
index 1d4e6cabf3..3ad240db01 100644
--- a/qmake/generators/makefile.cpp
+++ b/qmake/generators/makefile.cpp
@@ -1487,6 +1487,29 @@ MakefileGenerator::createObjectList(const QStringList &sources)
             int dl = fName.lastIndexOf(Option::dir_sep);
             if(dl != -1)
                 dir = fName.left(dl + 1);
+        } else if (project->isActiveConfig("object_parallel_to_source")) {
+            // The source paths are relative to the output dir, but we need source-relative paths
+            QString sourceRelativePath = fileFixify(*it, qmake_getpwd(), Option::output_dir);
+            sourceRelativePath = Option::fixPathToTargetOS(sourceRelativePath, false);
+
+            if (sourceRelativePath.startsWith(".." + Option::dir_sep))
+                sourceRelativePath = fileFixify(sourceRelativePath, FileFixifyAbsolute);
+
+            if (QDir::isAbsolutePath(sourceRelativePath))
+                sourceRelativePath.remove(0, sourceRelativePath.indexOf(Option::dir_sep) + 1);
+
+            dir = objdir; // We still respect OBJECTS_DIR
+
+            int lastDirSepPosition = sourceRelativePath.lastIndexOf(Option::dir_sep);
+            if (lastDirSepPosition != -1)
+                dir += sourceRelativePath.leftRef(lastDirSepPosition + 1);
+
+            if (!noIO()) {
+                // Ensure that the final output directory of each object exists
+                QString outRelativePath = fileFixify(dir, qmake_getpwd(), Option::output_dir);
+                if (!mkdir(outRelativePath))
+                    warn_msg(WarnLogic, "Cannot create directory '%s'", outRelativePath.toLatin1().constData());
+            }
         } else {
             dir = objdir;
         }