[cfe-dev] sizeof(long) in OpenCL C

[Michele Scandale]

On 08/29/2013 10:40 PM, Pekka Jääskeläinen wrote:
> On 08/29/2013 07:44 PM, David Tweed wrote:
>> However, it was felt that this wasn't an
>> area where the community wanted to put this in to the open source clang but
>> let different implementers do it according to their own designs in their own
>> code.
> 
> Could this be reconsidered? Is there a situation where one
> does not want to adhere to the OpenCL C types when compiling
> OpenCL C code? I do not understand the technical reasoning
> behind the decision to not apply the patch.
> 

Hi all,

I would like to join the discussion because I am interested in solving this
issue too. However my opinion is not in favor of the proposed patch (
http://lists.cs.uiuc.edu/pipermail/cfe-commits/Week-of-Mon-20130812/086263.html
). Being the question target-independent, I don't see the
TargetInfo::setForcedLangOptions the correct place for two reasons:
1. in CompilerInstance.cpp : 681-682 shows that having mutable target info is
not good
2. the method TargetInfo::setForcedLangOptions now is declared *virtual*,
allowing derived classes to overload it, making the the enforcement of language
options weak.

If (1) is still considered true, then TargetInfo::setForcedLangOptions should be
removed.
A possible way to achieve the same flexibility would be to have a wrapper class
"LanguageInfo" that handles the TargetInfo instance. This class would expose
methods to have knowledge about type size and alignment (like the TargetInfo
class) and whatever info that can be either target-dependent or not depending on
the language. These methods would simply check the current language
configuration in LangOptions and would redirect the query to the TargetInfo
class if no language enforcement is required otherwise will return the enforced
information.

If (1) is considered a too much strong requirement then the overloading of
TargetInfo::setForcedLangOptions should be avoided.

What do you think about this?

Thanks in advance.

Regards,
-Michele