There are some important issues to be aware of when compiling for x86 Solaris platforms.
Programs compiled with -xarch set to sse, sse2, sse2a,sse3, or beyond must be run only on platforms that provide these extensions and features.
Solaris OS releases starting with Solaris 9 4/04 are SSE/SSE2-enabled on Pentium 4-compatible platforms. Earlier versions of Solaris OS are not SSE/SSE2-enabled. If an instruction set selected by -xarch is not enabled in the running Solaris OS, the compiler will not be able to generate or link code for that instruction set.
If you compile and link in separate steps, always link using the compiler and with same -xarch setting to ensure that the correct startup routine is linked.
Numerical results on x86 might differ from results on SPARC due to the x86 80-bit floating-point registers. To minimize these differences, use the -fstore option or compile with -xarch=sse2 if the hardware supports SSE2.
Numerical results can also differ between Solaris and Linux because the intrinsic math libraries (for example, sin(x)) are not the same.