I can't say this is a bug it is changed behavior from before the new attribute scheme.
This issue may appear with other attributes. (there are other attributes that clang will now place
on each function)
If you run clang as a single pass to create a .ll and don't say -msoft-float, it puts the attribute use-soft-float=false on every function. (It used to be that in that case -msoft-float had no effect because those
attributes where not preserved in the IL. )
Then if you run llc and say -soft-float, what happens is that the code generator will compile everything as soft-float, but the value of the following will be false in XXXISelLowering getTargetMachine().Options.UseSoftFloat
When the constructor for XXXISelLowering is called, TM.Options.UseSoftFloat will be true.
What is interesting is that code for "make check" won't have any of the new attributes there so
it will work as before.
I was seeing this behavior and could not figure out how my tests could possibly pass if getTargetMachine().Options.UseSoftFloat was returning the wrong result.