Hi, I'm trying to make __builtin_apply work for my backend (especially gcc.dg/torture/stackalign/builtin-apply-2.c). My target saves unnamed args to the stack, and puts named arguments into registers (as much as possible). For example in the following testcase: void foo(char *name, double d, double e, double f, int g) { ... } void bar(char *name, ...) { __builtin_apply(foo, __builtin_apply_args(), 64); } In this example, foo expects first arguments to be in argument registers, but bar arguments are into the stack (only). expand_builtin_apply and expand_builtin_apply_args correctly copy incoming args block from the stack to outgoing_args block (stack) and set parameter registers as they were at the beginning of bar function, and then call foo (using the "standard" untyped_call). But there is no mechanism to copy incoming args from stack to argument registers. How and where to handle such a case which seems to depend on both caller and callee fndecl? Thanks in advance, Aurélien