[clang] Add getUnsignedPointerDiffType method
C11 standard refers to the unsigned counterpart of the type ptrdiff_t
in the paragraph 7.21.6.1p7 where it defines the format specifier %tu.
In Clang (in PrintfFormatString.cpp, lines 508-510) there is a FIXME for this case,
in particular, Clang didn't diagnose %tu issues at all, i.e.
it didn't emit any warnings on the code printf("%tu", 3.14).
In this diff we add a method getUnsignedPointerDiffType for getting the corresponding type
similarly to how it's already done in the other analogous cases (size_t, ssize_t, ptrdiff_t etc)
and fix -Wformat diagnostics for %tu plus the emitted fix-it as well.
Test plan: make check-all
Differential revision: https://reviews.llvm.org/D38270
llvm-svn: 314470
diff --git a/clang/lib/AST/ASTContext.cpp b/clang/lib/AST/ASTContext.cpp
index 82e7452..2a60799 100644
--- a/clang/lib/AST/ASTContext.cpp
+++ b/clang/lib/AST/ASTContext.cpp
@@ -4571,6 +4571,13 @@
return getFromTargetType(Target->getPtrDiffType(0));
}
+/// \brief Return the unique unsigned counterpart of "ptrdiff_t"
+/// integer type. The standard (C11 7.21.6.1p7) refers to this type
+/// in the definition of %tu format specifier.
+QualType ASTContext::getUnsignedPointerDiffType() const {
+ return getFromTargetType(Target->getUnsignedPtrDiffType(0));
+}
+
/// \brief Return the unique type for "pid_t" defined in
/// <sys/types.h>. We need this to compute the correct type for vfork().
QualType ASTContext::getProcessIDType() const {