[cfe-dev] Transparent union

[Ted Kremenek]

On Dec 18, 2007, at 3:41 AM, Sanghyeon Seo wrote:

>
> Other than this and too verbose format string warnings, All of Tcl 6.4
> (very old version, but build system is simple Makefile without any
> automagics) compiles, including -emit-llvm. Whether the result is
> correct is unknown, but Tcl has a complete test suite.

Hi Sanghyeon,

I am curious to get your opinion on the format string warnings.  GCC  
by default does not emit similar warnings without a special flag.   
Although the warnings issued for Tcl might actually be genuine (I  
myself will take a look at the warnings for Tcl sometime this week to  
see if they are real), the real question is whether or not you want to  
see them always emitted by default.  The intention of making these  
warnings on by default in clang is to encourage better programming by  
warning of dangerous or deprecated API usage, but I wonder if this  
makes sense in all cases, especially when compiling a third-party code  
base.  Currently, we don't have a comprehensive scheme of when we  
should issue such warnings which are auxiliary to standard parsing and  
type system errors, and we are evolving this scheme over time as the  
driver is used.

So I guess for the format string warnings, would you (and others)  
prefer that they were *not* on by default, and like GCC, require a  
special flag to the driver for them to be emitted?

Ted