[LLVMbugs] [Bug 2971] New: &((char*)0)[0] not regarded as static initializer

[Neil Booth]

bugzilla-daemon at cs.uiuc.edu wrote:-

> http://llvm.org/bugs/show_bug.cgi?id=2971
> 
>            Summary: &((char*)0)[0] not regarded as static initializer
>            Product: clang
>            Version: unspecified
>           Platform: All
>         OS/Version: All
>             Status: NEW
>           Severity: normal
>           Priority: P2
>          Component: LLVM Codegen
>         AssignedTo: unassignedbugs at nondot.org
>         ReportedBy: nunoplopes at sapo.pt
>                 CC: llvmbugs at cs.uiuc.edu
> 
> 
> The following code crashes clang:
> 
> typedef struct FuncDef FuncDef;
> struct FuncDef {};
> 
> void sqlite3RegisterDateTimeFunctions(void){
>   static FuncDef aDateTimeFuncs = {((void*)&((char*)0)[0])};
> }
> 
> 
> With the error message:
> clang: CGDecl.cpp:86: llvm::GlobalValue*
> clang::CodeGen::CodeGenFunction::GenerateStaticBlockVarDecl(const
> clang::VarDecl&, bool, const char*): Assertion
> `getContext().getLangOptions().CPlusPlus && "only C++ supports non-constant
> static initializers!"' failed.
> 
> (I'm not sure if this a duplicate or not. I have the strange feeling it's not
> the first time I'm seeing this bug..)

It's not a bug; casts must be to arithmetic type (it would be nice if
Clang were more explicit about the real problem, rather than just saying
it's no good...).

Neil.