Parameter attributes on Cfunction closures sticks

src/codegen.cpp

@@ -5180,9 +5180,48 @@ static Function* gen_cfun_wrapper(
  // add nest parameter (pointer to jl_value_t* data array) after sret arg
  assert(closure_types);
  std::vector<Type*> fargt_sig(sig.fargt_sig);
+
  fargt_sig.insert(fargt_sig.begin() + sig.sret, T_pprjlvalue);
+
+ // Shift LLVM attributes for parameters one to the right, as
+ // we are adding the extra nest parameter after sret arg.
+ std::vector<std::pair<unsigned, AttributeSet>> newAttributes;
+ newAttributes.reserve(attributes.getNumAttrSets() + 1);
+ auto it = attributes.index_begin();
+
+ // Skip past FunctionIndex
+ if (it == AttributeList::AttrIndex::FunctionIndex) {
+ ++it;
+ }
+
+ // Move past ReturnValue and parameter return value
+ for (;it < AttributeList::AttrIndex::FirstArgIndex + sig.sret; ++it) {
+ if (attributes.hasAttributes(it)) {
+ newAttributes.emplace_back(it, attributes.getAttributes(it));
+ }
+ }
+
+ // Add the new nest attribute
+ AttrBuilder attrBuilder;
+ attrBuilder.addAttribute(Attribute::Nest);
+ newAttributes.emplace_back(it, AttributeSet::get(jl_LLVMContext, attrBuilder));
+
+ // Shift forward the rest of the attributes
+ for(;it < attributes.index_end(); ++it) {
+ if (attributes.hasAttributes(it)) {
+ newAttributes.emplace_back(it + 1, attributes.getAttributes(it));
+ }
+ }
+
+ // Remember to add back FunctionIndex
+ if (attributes.hasAttributes(AttributeList::AttrIndex::FunctionIndex)) {
+ newAttributes.emplace_back(AttributeList::AttrIndex::FunctionIndex,
+ attributes.getAttributes(AttributeList::AttrIndex::FunctionIndex));
+ }
+
+ // Create the new AttributeList
+ attributes = AttributeList::get(jl_LLVMContext, newAttributes);
  functype = FunctionType::get(sig.sret ? T_void : sig.prt, fargt_sig, /*isVa*/false);
- attributes = attributes.addAttribute(jl_LLVMContext, 1 + sig.sret, Attribute::Nest);
  }
  else {
  functype = sig.functype();

test/ccall.jl

@@ -982,6 +982,26 @@ for (t, v) in ((Complex{Int32}, :ci32), (Complex{Int64}, :ci64),
  end
 end
 
+
+#issue 40164
+@testset "llvm parameter attributes on cfunction closures" begin
+ struct Struct40164
+ x::Cdouble
+ y::Cdouble
+ z::Cdouble
+ end
+
+ function test_40164()
+ ret = Struct40164[]
+ f = x::Struct40164 -> (push!(ret, x); nothing)
+ f_c = @cfunction($f, Cvoid, (Struct40164,))
+ ccall(f_c.ptr, Ptr{Cvoid}, (Struct40164,), Struct40164(0, 1, 2))
+ ret
+ end
+
+ @test test_40164() == [Struct40164(0, 1, 2)]
+end
+
 else
 
 @test_broken "cfunction: no support for closures on this platform"