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bug: -fast -msse does not warn

tp5
New Contributor I
806 Views
$ icc -xHost -msse
icc: command line warning #10120: overriding '-xHost' with '-msse'
icc: command line error: no files specified; for help type "icc -help"
$ icc -fast -msse
icc: command line error: no files specified; for help type "icc -help"

Because -fast is short for -xHost and some other options, it should also warn that -msse overrides.

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KitturGanesh
Employee
806 Views

Hi, 
I agree, to make the diagnostic output consistent with your previous command I will file this with the developers and will keep you updated accordingly, thanks.
_
Kittur

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TimP
Honored Contributor III
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As icc hasn't supported an sse option less than sse2 for several years, you would likely need to specify one of the specific sse options supported by icc. 

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KitturGanesh
Employee
806 Views

Tim, I agree with what you say!  

Hi, 
I thought I can file an issue assuming that the compiler can further elaborate the diagnostic to say a default (sse2) was used (which is why you don't see a warning on sse) but I doubt if they will do as the help/manual would specify what's default and the compiler cannot issue diagnostics for that (due to so many that have defaults and is implicitly understood by user).

_Kittur 

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tp5
New Contributor I
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I just used -msse as an example. It occurs with any such flag.

$ icc -fast -mavx
icc: command line error: no files specified; for help type "icc -help
$ icc -fast -xAVX
icc: command line error: no files specified; for help type "icc -help"
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KitturGanesh
Employee
806 Views

Hi,
BTW, looking at this now, with the command  "-fast -msse" for example, the compiler can as well make the message output consistent with "-xHost -msse" as -xHost is embedded in -fast as well and let the user know about overriding it to make it consistent.   Or the compiler can just output the message on missing files only and if satisfied can then output other overriding message accordingly. Anyways, I've filed an issue on this with the developers and will update you accordingly, thanks!

 

_Kittur 

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KitturGanesh
Employee
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Because -fast is short for -xHost and some other options

Hi, on your comment above, -fast actually contains:  "-ipo, -O3, -no-prec-div, -static, -fp-model fast=2, and -xHost". 
So, if you specify option "-fast -xSSE3", option -xSSE3 takes effect. However, if you specify "-xSSE3 -fast" option -xHost takes effect.

_Kittur

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