Review Request: 8005879: Add -DMAC_OS_X_VERSION_MAX_ALLOWED=1070 to builds on Mac

[Erik Joelsson]

On 2013-02-14 18:04, David DeHaven wrote:
>> Here are a series of patches that adds the following to all native compile lines on macosx:
>>
>> -DMAC_OS_X_VERSION_MAX_ALLOWED=1070 -DMAC_OS_X_VERSION_MIN_REQUIRED=1070
> I know I'm not a reviewer, but I have an opinion anyways :)
>
> Using "-mmacosx-version-min=10.7" seems more appropriate for the latter, this is passed to the linker as well which I believe sets version information in the Mach-O headers (in the form of a load command) to prevent it from being loaded on older systems. The MIN_REQUIRED macro is set to a value that matches what's passed to the -mmacosx-version-min argument, so it doesn't need to be provided.
>
>
The effect of the -mmacosx-version-min=10.7 when sent to the linker is 
to make any calls to newer APIs "softlinked". This means the library 
will still load fine on the older OS, but the application is responsible 
for only actually making the newer calls if they are available. This is 
a good feature if you knowingly want to support multiple versions of the 
OS and still use features in the newer OS when available. I do not 
believe we have the need for that and if we ever do, then these 
parameters will need to change.

/Erik