Make -Wformat walk the typedef chain when looking for size_t, etc.
Clang's -Wformat fix-its currently suggest using "%zu" for values of
type size_t (in C99 or C++11 mode). However, for a type such as
std::vector<T>::size_type, it does not notice that type is actually
typedeffed to size_t, and instead suggests a format for the underlying
type, such as "%lu" or "%u".
This commit makes the format string fix mechanism walk the typedef chain
so that it notices if the type is size_t, even if that isn't "at the
top".
llvm-svn: 160886
diff --git a/clang/lib/Analysis/FormatString.cpp b/clang/lib/Analysis/FormatString.cpp
index caceeac..a68b9bb 100644
--- a/clang/lib/Analysis/FormatString.cpp
+++ b/clang/lib/Analysis/FormatString.cpp
@@ -681,3 +681,37 @@
}
return true;
}
+
+bool FormatSpecifier::namedTypeToLengthModifier(QualType QT,
+ LengthModifier &LM) {
+ assert(isa<TypedefType>(QT) && "Expected a TypedefType");
+ const TypedefNameDecl *Typedef = cast<TypedefType>(QT)->getDecl();
+
+ for (;;) {
+ const IdentifierInfo *Identifier = Typedef->getIdentifier();
+ if (Identifier->getName() == "size_t") {
+ LM.setKind(LengthModifier::AsSizeT);
+ return true;
+ } else if (Identifier->getName() == "ssize_t") {
+ // Not C99, but common in Unix.
+ LM.setKind(LengthModifier::AsSizeT);
+ return true;
+ } else if (Identifier->getName() == "intmax_t") {
+ LM.setKind(LengthModifier::AsIntMax);
+ return true;
+ } else if (Identifier->getName() == "uintmax_t") {
+ LM.setKind(LengthModifier::AsIntMax);
+ return true;
+ } else if (Identifier->getName() == "ptrdiff_t") {
+ LM.setKind(LengthModifier::AsPtrDiff);
+ return true;
+ }
+
+ QualType T = Typedef->getUnderlyingType();
+ if (!isa<TypedefType>(T))
+ break;
+
+ Typedef = cast<TypedefType>(T)->getDecl();
+ }
+ return false;
+}
diff --git a/clang/lib/Analysis/PrintfFormatString.cpp b/clang/lib/Analysis/PrintfFormatString.cpp
index aa6d742..2a9644a 100644
--- a/clang/lib/Analysis/PrintfFormatString.cpp
+++ b/clang/lib/Analysis/PrintfFormatString.cpp
@@ -447,21 +447,8 @@
}
// Handle size_t, ptrdiff_t, etc. that have dedicated length modifiers in C99.
- if (isa<TypedefType>(QT) && (LangOpt.C99 || LangOpt.CPlusPlus0x)) {
- const IdentifierInfo *Identifier = QT.getBaseTypeIdentifier();
- if (Identifier->getName() == "size_t") {
- LM.setKind(LengthModifier::AsSizeT);
- } else if (Identifier->getName() == "ssize_t") {
- // Not C99, but common in Unix.
- LM.setKind(LengthModifier::AsSizeT);
- } else if (Identifier->getName() == "intmax_t") {
- LM.setKind(LengthModifier::AsIntMax);
- } else if (Identifier->getName() == "uintmax_t") {
- LM.setKind(LengthModifier::AsIntMax);
- } else if (Identifier->getName() == "ptrdiff_t") {
- LM.setKind(LengthModifier::AsPtrDiff);
- }
- }
+ if (isa<TypedefType>(QT) && (LangOpt.C99 || LangOpt.CPlusPlus0x))
+ namedTypeToLengthModifier(QT, LM);
// If fixing the length modifier was enough, we are done.
const analyze_printf::ArgTypeResult &ATR = getArgType(Ctx, IsObjCLiteral);
diff --git a/clang/lib/Analysis/ScanfFormatString.cpp b/clang/lib/Analysis/ScanfFormatString.cpp
index 066d5d6..5c7e6ef 100644
--- a/clang/lib/Analysis/ScanfFormatString.cpp
+++ b/clang/lib/Analysis/ScanfFormatString.cpp
@@ -382,21 +382,8 @@
}
// Handle size_t, ptrdiff_t, etc. that have dedicated length modifiers in C99.
- if (isa<TypedefType>(PT) && (LangOpt.C99 || LangOpt.CPlusPlus0x)) {
- const IdentifierInfo *Identifier = QT.getBaseTypeIdentifier();
- if (Identifier->getName() == "size_t") {
- LM.setKind(LengthModifier::AsSizeT);
- } else if (Identifier->getName() == "ssize_t") {
- // Not C99, but common in Unix.
- LM.setKind(LengthModifier::AsSizeT);
- } else if (Identifier->getName() == "intmax_t") {
- LM.setKind(LengthModifier::AsIntMax);
- } else if (Identifier->getName() == "uintmax_t") {
- LM.setKind(LengthModifier::AsIntMax);
- } else if (Identifier->getName() == "ptrdiff_t") {
- LM.setKind(LengthModifier::AsPtrDiff);
- }
- }
+ if (isa<TypedefType>(PT) && (LangOpt.C99 || LangOpt.CPlusPlus0x))
+ namedTypeToLengthModifier(PT, LM);
// If fixing the length modifier was enough, we are done.
const analyze_scanf::ScanfArgTypeResult &ATR = getArgType(Ctx);