overriding '/QxSSE4.2' with '/archSSE3'

[rase]

I have set the project options to /arch:SSE3, /QaxSSE4.1 and /QaxSSE4.2 (Intel I7-920 processor for compile and execution). During the compile step I receive the message
ifort: command line warning #10121: overriding '/QxSSE4.2' with '/archSSE3'
Aren't SSE4.1 and SSE4.2 more powerful than SSE3, as the numbers imply? Why are SSE4.1 and 4.2 replaced by SSE3?

[Steven_L_Intel1]

The correct way to specify this on the command line is:

/arch:SSE3 /QaxSSE4.1,SSE4.2

You will probably have to use the Command Line > Additional Options to do this.

However, I agree with Tim's private reply that while this is allowed, it may not have much benefit to have two very similar instruction sets as alternate code paths. Will you be running this program on other CPUs? If not, then just use /QxHost and be done with it,

[rase]

Timothy: thanks for the explanation. I see now clearer what's happening.
Steve: thanks, I will follow your advice.