[CentOS] Building for older versions

Mon Nov 23 17:10:00 UTC 2015
Nicolas Thierry-Mieg <Nicolas.Thierry-Mieg at imag.fr>

On 11/23/2015 06:00 PM, Michael Eager wrote:
> On 11/23/2015 08:06 AM, Nicolas Thierry-Mieg wrote:
>> On 11/23/2015 04:33 PM, Michael Eager wrote:
>>> Hi --
>>>
>>> I'm trying to build an application on CentOS 7 which
>>> can run on older versions of CentOS.  I'm running into
>>> problems with versioning of memcpy in Glibc.  Executables
>>> built on CentOS 7 require memcpy from glibc-2.14, which
>>> causes the program not to load on systems with older
>>> versions of glibc.
>>>
>>> My online search suggests to add an asm() with a .symver
>>> option to select memcpy from glibc-2.2.5 in each of the
>>> source files which reference memcpy().  This isn't practical
>>> with a program with tens of thousands of source files.
>>>
>>> Does anyone have a reasonable solution?
>>
>> IMO you should really be building your app on an older Centos version
>> (5 or 6). Then your binary
>> should run everywhere, though it may sometimes require installing a
>> -compat package.
>
> That causes a number of other problems,

can you please provide some details? I'm genuinely curious as I've been 
faced with this occasionally and the only problem I've encountered is 
having to install a few *-compat packages.
thanks.

> when the only issue is
> accessing a working version of memcpy from the installed glibc.