Patch by Roman Divacky:
Extend string-literal checking for printf() format string to handle conditional
ternary operators where both sides are literals.
This fixes PR 3319: http://llvm.org/bugs/show_bug.cgi?id=3319
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@62117 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaChecking.cpp b/lib/Sema/SemaChecking.cpp
index 5bb78cd..ff9d753 100644
--- a/lib/Sema/SemaChecking.cpp
+++ b/lib/Sema/SemaChecking.cpp
@@ -369,6 +369,51 @@
return false;
}
+// Handle i > 1 ? "x" : "y", recursivelly
+bool Sema::SemaCheckStringLiteral(Expr *E, CallExpr *TheCall, bool HasVAListArg,
+ unsigned format_idx) {
+
+ switch (E->getStmtClass()) {
+ case Stmt::ConditionalOperatorClass: {
+ ConditionalOperator *C = cast<ConditionalOperator>(E);
+ return SemaCheckStringLiteral(C->getLHS(), TheCall,
+ HasVAListArg, format_idx)
+ && SemaCheckStringLiteral(C->getRHS(), TheCall,
+ HasVAListArg, format_idx);
+ }
+
+ case Stmt::ImplicitCastExprClass: {
+ ImplicitCastExpr *Expr = dyn_cast<ImplicitCastExpr>(E);
+ return SemaCheckStringLiteral(Expr->getSubExpr(), TheCall, HasVAListArg,
+ format_idx);
+ }
+
+ case Stmt::ParenExprClass: {
+ ParenExpr *Expr = dyn_cast<ParenExpr>(E);
+ return SemaCheckStringLiteral(Expr->getSubExpr(), TheCall, HasVAListArg,
+ format_idx);
+ }
+
+ default: {
+ ObjCStringLiteral *ObjCFExpr = dyn_cast<ObjCStringLiteral>(E);
+ StringLiteral *StrE = NULL;
+
+ if (ObjCFExpr)
+ StrE = ObjCFExpr->getString();
+ else
+ StrE = dyn_cast<StringLiteral>(E);
+
+ if (StrE) {
+ CheckPrintfString(StrE, E, TheCall, HasVAListArg, format_idx);
+ return true;
+ }
+
+ return false;
+ }
+ }
+}
+
+
/// CheckPrintfArguments - Check calls to printf (and similar functions) for
/// correct use of format strings.
///
@@ -444,15 +489,9 @@
// C string (e.g. "%d")
// ObjC string uses the same format specifiers as C string, so we can use
// the same format string checking logic for both ObjC and C strings.
- ObjCStringLiteral *ObjCFExpr = dyn_cast<ObjCStringLiteral>(OrigFormatExpr);
- StringLiteral *FExpr = NULL;
+ bool isFExpr = SemaCheckStringLiteral(OrigFormatExpr, TheCall, HasVAListArg, format_idx);
- if(ObjCFExpr != NULL)
- FExpr = ObjCFExpr->getString();
- else
- FExpr = dyn_cast<StringLiteral>(OrigFormatExpr);
-
- if (FExpr == NULL) {
+ if (!isFExpr) {
// For vprintf* functions (i.e., HasVAListArg==true), we add a
// special check to see if the format string is a function parameter
// of the function calling the printf function. If the function
@@ -475,13 +514,18 @@
if (DeclRefExpr* DR = dyn_cast<DeclRefExpr>(OrigFormatExpr))
if (isa<ParmVarDecl>(DR->getDecl()))
return;
-
+
Diag(TheCall->getArg(format_idx)->getLocStart(),
diag::warn_printf_not_string_constant)
<< OrigFormatExpr->getSourceRange();
return;
}
+}
+void Sema::CheckPrintfString(StringLiteral *FExpr, Expr *OrigFormatExpr,
+ CallExpr *TheCall, bool HasVAListArg, unsigned format_idx) {
+
+ ObjCStringLiteral *ObjCFExpr = dyn_cast<ObjCStringLiteral>(OrigFormatExpr);
// CHECK: is the format string a wide literal?
if (FExpr->isWide()) {
Diag(FExpr->getLocStart(),