Comment # 12 on bug 1092541 from Michal Srb

(In reply to Richard Biener from comment #3)
> The new situation is that it considers functions without
> target attribute to be decorated with the effective target options of the
> compilation.

This would explain the situation, but the gcc invocation does not have any
target options. I tried to remove all unnecessary options and the error is
still happening with gcc invocation looking like this (removed -D, -I and -W
options for brevity):

    gcc -fno-strict-aliasing -fvisibility=hidden -O2 -g -c gen4_vertex.c -fPIC
-o
    .libs/gen4_vertex.o

(In reply to Richard Biener from comment #11)
> I wonder whether the package
> uses any of the -ffast-math options and thus if we could relax this
> condition with -funsafe-math-optimizations or so.

As far as I can see it does not use -ffast-math (as parameter or attribute). I
tried adding either -fexcess-precision=standard or -funsafe-math-optimizations,
but it still reports the same error.