My use case currently requires me to be able to parse the AST. As I mentioned, I almost have the problem solved. I modified the "createInvocationFromCommandLine" function and added "TheDriver.CCCIsCXX=true". The only problem is that the args in the CompilerInvocation object created are not in the correct order. All the C++ include arguments are put AFTER the source file and so they are not working. The "createInvocationFromArgs" is doing this. Is there any way this can be remedied?<div>
<br></div><div> On a completely different note, Can this be done using Libtooling? If yes, Can you please provide a small example. There is rarely any documentation on LibTooling and the Tooling API is much harder to understand than normal Clang API which is much more intuitive.</div>
<div><br></div><div>Regards,</div><div>Adil<br><br><div class="gmail_quote">On Thu, Oct 18, 2012 at 9:58 PM, Sean Silva <span dir="ltr"><<a href="mailto:silvas@purdue.edu" target="_blank">silvas@purdue.edu</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">Another problem that you are likely to run into is that there are some<br>
headers like stddef.h which are looked for in a hardcoded path<br>
relative to the binary itself, so you must either hardcode the path on<br>
your system in some way, or run your tool only in particular<br>
directories.<br>
<br>
The problem that you are having is probably the #1 most annoying thing<br>
for me about clang. When I was getting started with clang I spent more<br>
time than I wish to admit on exactly what you are trying to do now,<br>
and basically my conclusion was that Clang does not support this use<br>
case currently (i.e., using clang as a library to simply parse an<br>
arbitrary C++ file and then do stuff with the AST or whatever).<br>
libTooling was not around back then, so libTooling might be a way to<br>
accomplish what you want. You are going to waste a lot of time if you<br>
try to manually do this though---I certainly did.<br>
<br>
Someday, we may be able to say ParseFile("foo.cpp") which just gives<br>
you the ASTContext for the parsed file, but we currently do not, and<br>
it is a *really*, **really** hard problem to be able to make something<br>
like that "just work".<br>
<br>
A plugin is a way to get around this though, but your tool may or may<br>
not fit into the plugin model. If all you want though is to get the<br>
ASTContext and do something with it, then a plugin is the way to go<br>
currently.<br>
<span class="HOEnZb"><font color="#888888"><br>
-- Sean Silva<br>
</font></span><div class="HOEnZb"><div class="h5"><br>
On Thu, Oct 18, 2012 at 3:22 AM, Mohammad Adil <<a href="mailto:madil90@gmail.com">madil90@gmail.com</a>> wrote:<br>
> I've been looking at the source code of the Driver. What I have understood<br>
> till now is that the driver is created for the platform we are working on.<br>
> The driver can then build a compilation object from a list of arguments.<br>
> Inside this compilation object, there exists a toolchain specific to the<br>
> platform (e.g. Linux in my case) which has the job of inserting correct<br>
> system and C++ include paths. Is that correct? Let us say that I have build<br>
> such a compilation object. How can I create a CompilerInvocation or<br>
> CompilerInstance out of this such that it includes the information about all<br>
> default C and C++ paths? I see no way of using the driver to just create an<br>
> AST and parse it so the only way is to create a Driver and somehow create a<br>
> CompilerInstance out of it.<br>
><br>
><br>
> On Thu, Oct 18, 2012 at 1:09 AM, Manuel Klimek <<a href="mailto:klimek@google.com">klimek@google.com</a>> wrote:<br>
>><br>
>> On Wed, Oct 17, 2012 at 6:50 PM, David Blaikie <<a href="mailto:dblaikie@gmail.com">dblaikie@gmail.com</a>> wrote:<br>
>>><br>
>>> (readding cfe-dev)<br>
>>><br>
>>><br>
>>><br>
>>> On Wed, Oct 17, 2012 at 9:42 AM, Mohammad Adil <<a href="mailto:madil90@gmail.com">madil90@gmail.com</a>> wrote:<br>
>>> > What I am trying to do is to make a small program which parses the AST<br>
>>> > and<br>
>>> > does some rewriting to output modified code. How will I use the Driver<br>
>>> > in<br>
>>> > this case? All I want to do is to parse the AST.<br>
>>><br>
>>> I don't know off-hand what the best way to integrate the Driver's<br>
>>> lib/header discovery is, just that that's where the logic is.<br>
>>><br>
>>> The focus of Clang development with regard to "tools" like the one you<br>
>>> described is the Tooling infrastructure (overview of options & a link<br>
>>> to libTooling-specific information can be found here:<br>
>>> <a href="http://clang.llvm.org/docs/Tooling.html" target="_blank">http://clang.llvm.org/docs/Tooling.html</a> ). I'm not sure if that meets<br>
>>> the "standalone execution" scenario that you seem to be going for -<br>
>>> it's ideally meant to integrate with code already building using an<br>
>>> existing build system that has been modified to generate a database of<br>
>>> compilation commands. I /think/ it should also work standalone & still<br>
>>> do all the driver-based discovery, but I could be wrong.<br>
>><br>
>><br>
>> It does not fully do the driver-based discovery, but it'll usually work<br>
>> with the same flags that you provide to a normal clang call - and you can<br>
>> always specify options after "--" if you build the tool like in the<br>
>> tutorials.<br>
>><br>
>> Cheers,<br>
>> /Manuel<br>
>><br>
>>><br>
>>><br>
>>> > On Wed, Oct 17, 2012 at 9:39 PM, David Blaikie <<a href="mailto:dblaikie@gmail.com">dblaikie@gmail.com</a>><br>
>>> > wrote:<br>
>>> >><br>
>>> >> On Wed, Oct 17, 2012 at 9:29 AM, madil90 <<a href="mailto:madil90@gmail.com">madil90@gmail.com</a>> wrote:<br>
>>> >> > Hi,<br>
>>> >> > I am trying to parse a C++ code but clang doesn't recognize the<br>
>>> >> > C++<br>
>>> >> > types. Consider the following code<br>
>>> >> ><br>
>>> >> > #include <iostream><br>
>>> >> > #include <string><br>
>>> >> ><br>
>>> >> > int main()<br>
>>> >> > {<br>
>>> >> > string str;<br>
>>> >> > }<br>
>>> >> ><br>
>>> >> > clang gives an error at <iostream> and doesn't recognize the string<br>
>>> >> > type. To<br>
>>> >> > enable C++, I did "langOptions.CPlusPlus=1" and the code recognizes<br>
>>> >> > custom<br>
>>> >> > C++ classes. So how do I include default C++ paths?<br>
>>> >><br>
>>> >> I assume you're using clang as a library, rather than actually going<br>
>>> >> through the clang driver? The driver's where all (most) of the header<br>
>>> >> search logic is. You can extract the paths by simply asking clang what<br>
>>> >> command it used to invoke the frontend (I forget offhand, but there is<br>
>>> >> a verbose/print-commands option to clang) & just pass those in. But if<br>
>>> >> you want to make a tool using clang as a library & have the same<br>
>>> >> header/lib discovery that the clang command line program has, you'd<br>
>>> >> need to duplicate or reuse the logic in the driver.<br>
>>> >><br>
>>> >> - David<br>
>>> ><br>
>>> ><br>
>>> ><br>
>>> ><br>
>>> > --<br>
>>> > Mohammad Adil<br>
>>> > LUMS SSE<br>
>>> ><br>
>>><br>
>>> _______________________________________________<br>
>>> cfe-dev mailing list<br>
>>> <a href="mailto:cfe-dev@cs.uiuc.edu">cfe-dev@cs.uiuc.edu</a><br>
>>> <a href="http://lists.cs.uiuc.edu/mailman/listinfo/cfe-dev" target="_blank">http://lists.cs.uiuc.edu/mailman/listinfo/cfe-dev</a><br>
>><br>
>><br>
><br>
><br>
><br>
> --<br>
> Mohammad Adil<br>
> LUMS SSE<br>
><br>
><br>
> _______________________________________________<br>
> cfe-dev mailing list<br>
> <a href="mailto:cfe-dev@cs.uiuc.edu">cfe-dev@cs.uiuc.edu</a><br>
> <a href="http://lists.cs.uiuc.edu/mailman/listinfo/cfe-dev" target="_blank">http://lists.cs.uiuc.edu/mailman/listinfo/cfe-dev</a><br>
><br>
</div></div></blockquote></div><br><br clear="all"><div><br></div>-- <br>Mohammad Adil<div>LUMS SSE</div><br>
</div>