[PATCH] Don't emit prologues/epilogues for naked functions (PR18791, PR20028)

[Hans Wennborg]

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Comment at: lib/Sema/SemaStmtAsm.cpp:414
@@ +413,3 @@
+          Diag(Id.getLocStart(), diag::err_asm_naked_parm_ref);
+          Diag(Func->getAttr<NakedAttr>()->getLocation(), diag::note_attribute);
+        }
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rnk wrote:
> thakis wrote:
> > Do you need to ` Func->setInvalidDecl();` here too?
> Let's do that.
I commented on the email thread that maybe "return ExprError()" is the right thing to do here. That seems to be how the rest of this function does it.

http://reviews.llvm.org/D5183