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</o:shapelayout></xml><![endif]--></head><body lang=EN-GB link=blue vlink=purple><div class=WordSection1><p class=MsoNormal>I am trying to implement the lifetime marker insertion for unnamed temporaries in order to reduce stack consumption.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Inserting the lifetime.begin marker is the easy part; on the other hand, inserting the lifetime.end gets a bit more complicated, as it involves scoping , exception handling and lifetime extension.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Ideally, the lifetime.end marker should be inserted when the scope is exited, after the cleanups have been run. The problem is that in some cases, an object with a trivial destructor for example, there is … no cleanup. The existence of cleanups appears in the AST with the ExpWithCleanups, which wraps the underlying MaterializeTemporaryExpr.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>This is used in CodeGenFunction::EmitLValue to start a new RunCleanupsScope when visiting an ExpWithCleanups. My problem is how can I add a RunCleanupScope for MaterializeTemporaryExpr that are not part of an ExpWithCleanups. I can not always add a new scope, because it would mess-up the cleanup ordering --- when there are cleanups, the lifetime.end marker should be emitted after the destructor.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Is there anything obvious I am missing ?<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Any hints would be welcome. <o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Cheers,<o:p></o:p></p><p class=MsoNormal><span style='mso-fareast-language:EN-GB'>--<o:p></o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-GB'>Arnaud A. de Grandmaison<o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>