GCC v4.4.0 Platform Support and Backwards Compatibility

[David Daney]

Myers Andrew NGA-AES USA CTR wrote:
> We are running GCC v3.4.4 on the Red Hat Enterprise Linux 4 64-Bit
> platform.  Questions specific to the 64-bit version are...
> 
> 1) Does v4.4.0 support the Red Hat Enterprise Linux 4 (64-Bit) platform?

It should, but you could ask the vendor for a more definitive answer.

> 2) Is code developed under GCC v3.4.4 guaranteed to compile under GCC
> v4.4.0?
> 

GCC doesn't offer any hard guarantees.  The license explains this.

That said, the answer is no.  GCC tries to offer backwards compatibility 
while adhering to the various standards that govern the languages it 
implements, but in some cases you will have to change your code to be 
able to use GCC-4.4.  The common case is code that is not standards 
compliant might compile under GCC-3.4 but because GCC-4.4 is more strict 
with regard to the standards it implements than previous versions, the 
code would be rejected.

David Daney