MySQL Bugs: #74170: st_mysql_show_var::value should be void* not char*

Bug #74170	st_mysql_show_var::value should be void* not char*
Submitted:	1 Oct 2014 6:53	Modified:	2 Nov 2014 16:24
Reporter:	Hartmut Holzgraefe	Email Updates:
Status:	No Feedback	Impact on me:	None
Category:	MySQL Server: Compiling	Severity:	S3 (Non-critical)
Version:	5.6.20, all?	OS:	Any
Assigned to:		CPU Architecture:	Any

Description:
... as conversion from function pointer to char* is not allowed in C / C++

How to repeat:
In my plugin I have:

static struct st_mysql_show_var my_plugin_statvars[]=
{
    {"my_show_entry", (char *)&show_my_entry, SHOW_FUNC}
}

with C I'm getting 

my_plugin.c:131:32: warning: ISO C forbids conversion of function pointer to object pointer type [-Wpedantic]
    {"my_show_entry", (char *)&show_my_entry, SHOW_FUNC}
                      ^

and with C++

my_plugin.cc:131:41: warning: ISO C++ forbids casting between pointer-to-function and pointer-to-object [enabled by default]
    {"my_show_entry", (char *)&show_my_entry, SHOW_FUNC}
                               ^

Suggested fix:
Change st_mysql_show_var::value type to void* to allow writing of warning-free plugin code

Dear Mr. Holzgraefe,

I have fully analyzed your bug report. It seems to be fully justified, but for full verification, I do need to know a version of your C / C++ compiler.

Many thanks in advance.

No feedback was provided for this bug for over a month, so it is
being suspended automatically. If you are able to provide the
information that was originally requested, please do so and change
the status of the bug back to "Open".