https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68390
Bug ID: 68390
Summary: Incorrect code due to indirect tail call of varargs
function with hard float ABI
Product: gcc
Version: 6.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: target
Assignee: unassigned at gcc dot gnu.org
Reporter: kugan at gcc dot gnu.org
Target Milestone: ---
__attribute__ ((noinline))
double direct(int x, ...)
{
return x*x;
}
__attribute__ ((noinline))
double broken(double (*indirect)(int x, ...), int v)
{
return indirect(v);
}
int main ()
{
double d1, d2;
int i = 2;
d1 = broken (direct, i);
if (d1 != i*i)
{
__builtin_abort ();
}
return 0;
}
Please note that we have a sibcall from "broken" to "indirect".
"direct" is variadic function so it is conforming to AAPCS base standard.
"broken" is a non-variadic function and will return the value in
floating point register for TARGET_HARD_FLOAT. Thus we should not be
doing sibcall here.
