[Linux-ha-dev] [PATCH] [glue] Fix compilation with GCC 4.6

[Pádraig Brady]

On 30/06/11 20:33, Lars Ellenberg wrote:
> On Wed, Jun 29, 2011 at 12:55:08PM +0100, Pádraig Brady wrote:
>> On 29/06/11 11:56, Lars Ellenberg wrote:
>>> On Tue, Jun 28, 2011 at 01:44:23AM +0100, Pádraig Brady wrote:
>>>> The attached patch fixes compilation -Werrors with GCC 4.6
>>>>
>>>> cheers,
>>>> Pádraig.
>>>>
>>>
>>>> Fix compilation with GCC 4.6
>>>>
>>>> avoid -Werror=unused-but-set-variable issues
>>>> remove -Wcast-qual which caused issues with copyHostList()
>>>
>>> Care to explain or show those "issues"?
>>
>> All uses of copyHostList error like:
>>
>> apcsmart.c: In function 'apcsmart_hostlist':
>> apcsmart.c:722:34: error: to be safe all intermediate pointers in cast from 'char **' to 'const char **' must be 'const' qualified [-Werror=cast-qual]
> 
> From the gcc 4.5 documentation:
> -Wcast-qual
> 	Warn whenever a pointer is cast so as to remove a type qualifier from the target
> 	type. For example, warn if a const char * is cast to an ordinary char *.
> 	Also warn when making a cast which introduces a type qualifier in an unsafe
> 	way. For example, casting char ** to const char ** is unsafe, as in this ex-
> 	ample:
> 		/* p is char ** value. */
> 		const char **q = (const char **) p;
> 		/* Assignment of readonly string to const char * is OK.
> 		*q = "string";
> 		/* Now char** pointer points to read-only memory. */
> 		**p = ’b’;
> 
> So apparently it needs to be
> 
> include/stonith/stonith_plugin.h:
>  struct StonithImports_s {
>  ...
> -	char **(*CopyHostList)(const char ** hlstring);
> +	char **(*CopyHostList)(const char * const * hlstring);
> 
> And the callers have to be adjusted accordingly?
> Could you check if that works?

Sure, that would work but would involve a lot of changes I think.
I was unsure how changing this interface might affect users
outside this project, but if that's OK I'll go ahead
and change that (tomorrow when I'm more awake).

Oh and originally I forgot to mention that
these changes are required to get this project to
compile on Fedora 15.

cheers,
Pádraig.