Recent devel/libclc update breaking graphics/dri - it seems

[Tommy Scheunemann]

Hi every1,

it seems - hopefully not just for me (sorry) - the recent devel/libclc 
update breaks graphics/dri.
Upon updating libclc, llvm40 gets lurked into the system and graphics/dri 
gets rebuilt, using llvm40 - even if 3.9 is installed - for compilation.
The compile then stops with.

--- SNIP ---
In file included from draw/draw_llvm.c:45:
./gallivm/lp_bld_intr.h:69:20: error: unknown type name 'LLVMAttribute'; 
did you mean 'LLVMAttribu
teRef'?
                    LLVMAttribute attr);
                    ^~~~~~~~~~~~~
                    LLVMAttributeRef
/usr/local/llvm40/include/llvm-c/Types.h:116:40: note: 'LLVMAttributeRef' 
declared here
typedef struct LLVMOpaqueAttributeRef *LLVMAttributeRef;
                                        ^
draw/draw_llvm.c:1577:10: error: implicit declaration of function 
'LLVMAddAttribute' is invalid in
  C99 [-Werror,-Wimplicit-function-declaration]
          LLVMAddAttribute(LLVMGetParam(variant_func, i),
--- SNIP ---

Even manually upgrading libclc, deinstalling llvm40 and reinstalling 
llvm39, at the latest when it comes to graphics/dri llvm40 gets pulled in 
again and the compile run fails.

My guess (guess, crytal ball, lottery) is the update of libclc breaks 
graphics/dri due to llvm40 dependencies.

Any useful idea on how to fix this ? My second guess (again with a crystal 
ball playing lottery) is that mesa 13.0.6 isn't playing nice with llvm4 
atm.

Kind regards