Ensure that debugger calls to signature-less functions default to
passing arguments in the fixed style.
We have an abstraction for deciding this, but it's (1) deep in
IR-generation, (2) necessarily tied to exact argument lists, and
(3) triggered by unprototyped function types, which we can't
legitimately make in C++ mode. So this solution, wherein Sema
rewrites the function type to an exact prototype but leaves the
variadic bit enabled so as to request x86-64-like platforms to
pass the extra variadic info, is very much a hack, but it's one
that works in practice on the platforms that LLDB will support
in the medium term --- the only place we know of where it's a
problem is instance methods in Windows, where variadic functions
are implicitly cdecl. We may have a more abstracted base on which
to build a solution by then.
rdar://13731520
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@185112 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/TargetInfo.h b/lib/CodeGen/TargetInfo.h
index ab7b061..a7fb886 100644
--- a/lib/CodeGen/TargetInfo.h
+++ b/lib/CodeGen/TargetInfo.h
@@ -171,6 +171,13 @@
/// arguments in %al. On these platforms, it is desireable to
/// call unprototyped functions using the variadic convention so
/// that unprototyped calls to varargs functions still succeed.
+ ///
+ /// Relatedly, platforms which pass the fixed arguments to this:
+ /// A foo(B, C, D);
+ /// differently than they would pass them to this:
+ /// A foo(B, C, D, ...);
+ /// may need to adjust the debugger-support code in Sema to do the
+ /// right thing when calling a function with no know signature.
virtual bool isNoProtoCallVariadic(const CodeGen::CallArgList &args,
const FunctionNoProtoType *fnType) const;