Stop updating timestamps of generated files that haven't changed

This is a change in preparation for improved incremental builds,
where modifying one typesystem XML file will not force rebuilding
all generated cpp files.

The previous logic was incorrect, file timestamps should not
be updated if the generated files are unchanged, instead the build
rules need to be adapted to prevent unnecessary rebuilds.

Change-Id: Ia47f8ff1970e974d0e617b6891ab58666da3b1ff
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@qt.io>
Reviewed-by: Christian Tismer <tismer@stackless.com>

1 files changed, 1 insertions, 14 deletions

diff --git a/sources/shiboken2/generator/generator.cpp b/sources/shiboken2/generator/generator.cpp
index 85a8c4769..8b37b44e0 100644
--- a/sources/shiboken2/generator/generator.cpp
+++ b/sources/shiboken2/generator/generator.cpp
@@ -395,20 +395,7 @@ bool Generator::generateFileForContext(GeneratorContext &context)
 
     generateClass(fileOut.stream, context);
 
-    FileOut::State state = fileOut.done();
-    switch (state) {
-    case FileOut::Failure:
-        return false;
-    case FileOut::Unchanged:
-        // Even if contents is unchanged, the last file modification time should be updated,
-        // so that the build system can rely on the fact the generated file is up-to-date.
-        fileOut.touch();
-        break;
-    case FileOut::Success:
-        break;
-    }
-
-    return true;
+    return fileOut.done() != FileOut::Failure;
 }
 
 QString Generator::getFileNameBaseForSmartPointer(const AbstractMetaType *smartPointerType,