This uses dg-additional-options, not dg-options which overrides target specific flags added by dg-require-effective-target vect_float.
Tested on x86_64-unknown-linux-gnu, applied. Richard. 2013-04-03 Richard Biener <rguent...@suse.de> * g++.dg/vect/slp-pr56812.cc: Use dg-additional-options. Index: gcc/testsuite/g++.dg/vect/slp-pr56812.cc =================================================================== --- gcc/testsuite/g++.dg/vect/slp-pr56812.cc (revision 197397) +++ gcc/testsuite/g++.dg/vect/slp-pr56812.cc (working copy) @@ -1,6 +1,6 @@ /* { dg-do compile } */ /* { dg-require-effective-target vect_float } */ -/* { dg-options "-O3 -funroll-loops -fdump-tree-slp-details" } */ +/* { dg-additional-options "-O3 -funroll-loops -fvect-cost-model" } */ class mydata { public: