implementation of format_arg for ObjC methods/functions.
Still more to do.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@72173 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaDeclAttr.cpp b/lib/Sema/SemaDeclAttr.cpp
index c509931..99b4d77 100644
--- a/lib/Sema/SemaDeclAttr.cpp
+++ b/lib/Sema/SemaDeclAttr.cpp
@@ -99,6 +99,12 @@
return cast<ObjCMethodDecl>(d)->param_begin()[Idx]->getType();
}
+static QualType getFunctionOrMethodResultType(Decl *d) {
+ if (const FunctionType *FnTy = getFunctionType(d))
+ return cast<FunctionProtoType>(FnTy)->getResultType();
+ return cast<ObjCMethodDecl>(d)->getResultType();
+}
+
static bool isFunctionOrMethodVariadic(Decl *d) {
if (const FunctionType *FnTy = getFunctionType(d)) {
const FunctionProtoType *proto = cast<FunctionProtoType>(FnTy);
@@ -1069,6 +1075,69 @@
d->addAttr(::new (S.Context) CleanupAttr(FD));
}
+/// Handle __attribute__((format_arg((idx)))) attribute
+/// based on http://gcc.gnu.org/onlinedocs/gcc/Function-Attributes.html
+static void HandleFormatArgAttr(Decl *d, const AttributeList &Attr, Sema &S) {
+ if (Attr.getNumArgs() != 1) {
+ S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 1;
+ return;
+ }
+ if (!isFunctionOrMethod(d) || !hasFunctionProto(d)) {
+ S.Diag(Attr.getLoc(), diag::warn_attribute_wrong_decl_type)
+ << Attr.getName() << 0 /*function*/;
+ return;
+ }
+ // FIXME: in C++ the implicit 'this' function parameter also counts.
+ // this is needed in order to be compatible with GCC
+ // the index must start with 1.
+ unsigned NumArgs = getFunctionOrMethodNumArgs(d);
+ unsigned FirstIdx = 1;
+ // checks for the 2nd argument
+ Expr *IdxExpr = static_cast<Expr *>(Attr.getArg(0));
+ llvm::APSInt Idx(32);
+ if (!IdxExpr->isIntegerConstantExpr(Idx, S.Context)) {
+ S.Diag(Attr.getLoc(), diag::err_attribute_argument_n_not_int)
+ << "format" << 2 << IdxExpr->getSourceRange();
+ return;
+ }
+
+ if (Idx.getZExtValue() < FirstIdx || Idx.getZExtValue() > NumArgs) {
+ S.Diag(Attr.getLoc(), diag::err_attribute_argument_out_of_bounds)
+ << "format" << 2 << IdxExpr->getSourceRange();
+ return;
+ }
+
+ unsigned ArgIdx = Idx.getZExtValue() - 1;
+
+ // make sure the format string is really a string
+ QualType Ty = getFunctionOrMethodArgType(d, ArgIdx);
+
+ bool not_nsstring_type = !isNSStringType(Ty, S.Context);
+ if (not_nsstring_type &&
+ !isCFStringType(Ty, S.Context) &&
+ (!Ty->isPointerType() ||
+ !Ty->getAsPointerType()->getPointeeType()->isCharType())) {
+ // FIXME: Should highlight the actual expression that has the wrong type.
+ S.Diag(Attr.getLoc(), diag::err_format_attribute_not)
+ << (not_nsstring_type ? "a string type" : "an NSString")
+ << IdxExpr->getSourceRange();
+ return;
+ }
+ Ty = getFunctionOrMethodResultType(d);
+ if (!isNSStringType(Ty, S.Context) &&
+ !isCFStringType(Ty, S.Context) &&
+ (!Ty->isPointerType() ||
+ !Ty->getAsPointerType()->getPointeeType()->isCharType())) {
+ // FIXME: Should highlight the actual expression that has the wrong type.
+ S.Diag(Attr.getLoc(), diag::err_format_attribute_result_not)
+ << (not_nsstring_type ? "string type" : "NSString")
+ << IdxExpr->getSourceRange();
+ return;
+ }
+
+ d->addAttr(::new (S.Context) FormatArgAttr(Idx.getZExtValue()));
+}
+
/// Handle __attribute__((format(type,idx,firstarg))) attributes
/// based on http://gcc.gnu.org/onlinedocs/gcc/Function-Attributes.html
static void HandleFormatAttr(Decl *d, const AttributeList &Attr, Sema &S) {
@@ -1653,6 +1722,7 @@
break;
case AttributeList::AT_fastcall: HandleFastCallAttr (D, Attr, S); break;
case AttributeList::AT_format: HandleFormatAttr (D, Attr, S); break;
+ case AttributeList::AT_format_arg: HandleFormatArgAttr (D, Attr, S); break;
case AttributeList::AT_gnu_inline: HandleGNUInlineAttr(D, Attr, S); break;
case AttributeList::AT_mode: HandleModeAttr (D, Attr, S); break;
case AttributeList::AT_nonnull: HandleNonNullAttr (D, Attr, S); break;