Merge pull request #16167 from JuliaLang/jn/ccallable

update `@ccallable` to expect a return type declaration

base/c.jl

@@ -209,11 +209,7 @@ function ccallable(f::Function, rt::Type, argt::Type, name::Union{AbstractString
  ccall(:jl_extern_c, Void, (Any, Any, Any, Cstring), f, rt, argt, name)
 end
 
-function ccallable(f::Function, argt::Type, name::Union{AbstractString,Symbol}=string(f))
- ccall(:jl_extern_c, Void, (Any, Ptr{Void}, Any, Cstring), f, C_NULL, argt, name)
-end
-
-macro ccallable(def)
+macro ccallable(rt, def)
  if isa(def,Expr) && (def.head === :(=) || def.head === :function)
  sig = def.args[1]
  if sig.head === :call
@@ -227,7 +223,7 @@ macro ccallable(def)
  end
  return quote
  $(esc(def))
- ccallable($(esc(name)), $(Expr(:curly, :Tuple, map(esc, at)...)))
+ ccallable($(esc(name)), $(esc(rt)), $(Expr(:curly, :Tuple, map(esc, at)...)), $(string(name)))
  end
  end
  end

base/deprecated.jl

@@ -1085,6 +1085,32 @@ end
 #15995
 @deprecate symbol Symbol
 
+macro ccallable(def)
+ depwarn("@ccallable requires a return type", Symbol("@ccallable"))
+ if isa(def,Expr) && (def.head === :(=) || def.head === :function)
+ sig = def.args[1]
+ if sig.head === :call
+ name = sig.args[1]
+ at = map(sig.args[2:end]) do a
+ if isa(a,Expr) && a.head === :(::)
+ a.args[2]
+ else
+ :Any
+ end
+ end
+ return quote
+ $(esc(def))
+ let name = $(esc(name)), tt = $(Expr(:curly, :Tuple, map(esc, at)...))
+ rt = return_types(name, tt)
+ length(rt) == 1 || error("function not ccallable")
+ ccallable(name, rt[1], tt)
+ end
+ end
+ end
+ end
+ error("expected method definition in @ccallable")
+end
+
 # During the 0.5 development cycle, do not add any deprecations below this line
 # To be deprecated in 0.6
 

src/cgutils.cpp

@@ -406,7 +406,13 @@ static Type *julia_struct_to_llvm(jl_value_t *jt, bool *isboxed)
  }
 #ifndef NDEBUG
  // If LLVM and Julia disagree about alignment, much trouble ensues, so check it!
- unsigned llvm_alignment = jl_ExecutionEngine->getDataLayout().getABITypeAlignment((Type*)jst->struct_decl);
+ const DataLayout &DL =
+#ifdef LLVM36
+ jl_ExecutionEngine->getDataLayout();
+#else
+ *jl_ExecutionEngine->getDataLayout();
+#endif
+ unsigned llvm_alignment = DL.getABITypeAlignment((Type*)jst->struct_decl);
  unsigned julia_alignment = jst->alignment;
  assert(llvm_alignment==julia_alignment);
 #endif

test/llvmcall.jl

@@ -143,19 +143,15 @@ confuse_declname_parsing()
 
 
 module ObjLoadTest
- using Base.Test
- using Base.llvmcall
- here = dirname(@__FILE__)
+ using Base: Test, llvmcall, @ccallable
  didcall = false
- function callback()
+ @ccallable Void function jl_the_callback()
  global didcall
  didcall = true
  nothing
  end
- Base.ccallable(callback,Void,Tuple{},:jl_the_callback)
- Base.ccallable(callback,Void,Tuple{},:_jl_the_callback)
  # Make sure everything up until here gets compiled
- callback(); didcall = false
+ jl_the_callback(); didcall = false
  function do_the_call()
  llvmcall(
  (""" declare void @jl_the_callback()""",
@@ -169,7 +165,7 @@ module ObjLoadTest
 end
 
 # Test for proper parenting
-let
+if VersionNumber(Base.libllvm_version) >= v"3.6" # llvm 3.6 changed the syntax for a gep, so just ignore this test on older versions
  function foo()
  # this IR snippet triggers an optimization relying
  # on the llvmcall function having a parent module
@@ -179,4 +175,6 @@ let
  Void, Tuple{})
  end
  code_llvm(DevNull, foo, ())
+else
+ println("INFO: skipping gep parentage test on llvm < 3.6")
 end