Defining build options based on available compiler version

[Jussi Lehtola]

Hi,


I tried using 
 %global gccver %(gcc -dumpversion)
 %if %{gccver} >= 4.6.0
  foo here
 %endif

to conditionalize usage of quadruple precision support in a spec file
that ships on multiple distros, but the comparison gives the error

 parseExpressionBoolean returns -1

Is there a way to check if the gcc version is sufficient with some rpm
macro?
-- 
Jussi Lehtola
Fedora Project Contributor
jussilehtola at fedoraproject.org