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<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Hi,<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Ping^2. Chandler, if you don’t have time to complete this review
could someone else please do it? It’s been sitting around for quite a while
now.<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Cheers,<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>James<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
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<div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0cm 0cm 0cm'>
<p class=MsoNormal><b><span lang=EN-US style='font-size:10.0pt;font-family:
"Tahoma","sans-serif"'>From:</span></b><span lang=EN-US style='font-size:10.0pt;
font-family:"Tahoma","sans-serif"'> cfe-commits-bounces@cs.uiuc.edu
[mailto:cfe-commits-bounces@cs.uiuc.edu] <b>On Behalf Of </b>James Molloy<br>
<b>Sent:</b> 01 February 2012 10:03<br>
<b>To:</b> 'Chandler Carruth'<br>
<b>Cc:</b> juli@clockworksquid.com; cfe-commits@cs.uiuc.edu;
ken.dyck@onsemi.com<br>
<b>Subject:</b> Re: [cfe-commits] [PATCH] Fix tag decls/enum constants in
function prototypes<o:p></o:p></span></p>
</div>
</div>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Hi Chandler,<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>The simple answer is that at the point of parsing the function
parameter type (which these decls are), the current context is just the
translation unit. There is no prototype context entered.<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Even function parameters (ParmDecls) get pinned to the
translation unit scope – CurContext.isTranslationUnit() is true when Sema is
about to create a function parameter and there’s even this comment which makes
that state tautologous:<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'> // Temporarily put parameter variables in the translation
unit, not<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'> // the enclosing context. This prevents them from
accidentally<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'> // looking like class members in C++.<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'> ParmVarDecl *New =
CheckParameter(Context.getTranslationUnitDecl(),<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>So basically, Clang doesn’t have a good mechanism for this and my
patch just uses the same mechanism as is already there. I’m not proficient
enough with Clang to rewrite part of the AST structure to make both function
parameters and decls in parameters less hacky.<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Cheers,<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>James<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0cm 0cm 0cm'>
<p class=MsoNormal><b><span lang=EN-US style='font-size:10.0pt;font-family:
"Tahoma","sans-serif"'>From:</span></b><span lang=EN-US style='font-size:10.0pt;
font-family:"Tahoma","sans-serif"'> Chandler Carruth [mailto:chandlerc@google.com]
<br>
<b>Sent:</b> 01 February 2012 08:43<br>
<b>To:</b> James Molloy<br>
<b>Cc:</b> juli@clockworksquid.com; cfe-commits@cs.uiuc.edu;
ken.dyck@onsemi.com<br>
<b>Subject:</b> Re: [cfe-commits] [PATCH] Fix tag decls/enum constants in
function prototypes<o:p></o:p></span></p>
</div>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal style='margin-bottom:12.0pt'>Haven't yet done a full review,
sorry for the delays, but wanted to ask one question that jumped out at me.
Maybe you can explain and save me the trouble of tracking it down.<o:p></o:p></p>
<div>
<p class=MsoNormal>On Tue, Jan 31, 2012 at 1:41 AM, James Molloy <<a
href="mailto:james.molloy@arm.com">james.molloy@arm.com</a>> wrote:<o:p></o:p></p>
<p class=MsoNormal>This is due to a hack in the parser that hangs such tags on
the translation unit because no proper declcontext is available at that point.
I've modified my code so it catches this and unhooks them from the translation
unit, so they don't get visited twice and the output is better.<o:p></o:p></p>
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<p class=MsoNormal><o:p> </o:p></p>
<div>
<p class=MsoNormal>It would seem more clean to go in and fix the code that
attaches these to the translation unit to not do so? The current pattern seems
very inconsistent. It also means we're mutating the AST in weird ways. That
makes me nervous. I'd essentially like to see far fewer conditionals when
handling these declarations. We should be able to unconditionally set up the
lexical context, attach to the function, and push onto the scope... If there
are conditions on these steps, I would benefit from comments documenting why we
don't have consistent behavior...<o:p></o:p></p>
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