Update equality and relationship comparisons of pointers to reflect
C++ semantics, eliminating an extension diagnostic that doesn't match
C++ semantics (ordered comparison with NULL) and tightening some
extwarns to errors in C++ to match GCC and maintain conformance in
SFINAE contexts. Fixes <rdar://problem/7941392>.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@106050 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/clang/Basic/DiagnosticSemaKinds.td b/include/clang/Basic/DiagnosticSemaKinds.td
index 4ad76e4..d64a539 100644
--- a/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/include/clang/Basic/DiagnosticSemaKinds.td
@@ -2087,8 +2087,12 @@
"ordered comparison of function pointers (%0 and %1)">;
def ext_typecheck_comparison_of_fptr_to_void : Extension<
"equality comparison between function pointer and void pointer (%0 and %1)">;
+def err_typecheck_comparison_of_fptr_to_void : Error<
+ "equality comparison between function pointer and void pointer (%0 and %1)">;
def ext_typecheck_comparison_of_pointer_integer : ExtWarn<
"comparison between pointer and integer (%0 and %1)">;
+def err_typecheck_comparison_of_pointer_integer : Error<
+ "comparison between pointer and integer (%0 and %1)">;
def ext_typecheck_comparison_of_distinct_pointers : ExtWarn<
"comparison of distinct pointer types (%0 and %1)">;
def ext_typecheck_cond_incompatible_operands : ExtWarn<
diff --git a/lib/Sema/SemaExpr.cpp b/lib/Sema/SemaExpr.cpp
index c13520e..bb5fa71 100644
--- a/lib/Sema/SemaExpr.cpp
+++ b/lib/Sema/SemaExpr.cpp
@@ -5408,9 +5408,8 @@
bool RHSIsNull = rex->isNullPointerConstant(Context,
Expr::NPC_ValueDependentIsNull);
- // All of the following pointer related warnings are GCC extensions, except
- // when handling null pointer constants. One day, we can consider making them
- // errors (when -pedantic-errors is enabled).
+ // All of the following pointer-related warnings are GCC extensions, except
+ // when handling null pointer constants.
if (lType->isPointerType() && rType->isPointerType()) { // C99 6.5.8p2
QualType LCanPointeeTy =
Context.getCanonicalType(lType->getAs<PointerType>()->getPointeeType());
@@ -5424,10 +5423,19 @@
(LCanPointeeTy->isVoidType() || RCanPointeeTy->isVoidType())) {
// Valid unless comparison between non-null pointer and function pointer
// This is a gcc extension compatibility comparison.
+ // In a SFINAE context, we treat this as a hard error to maintain
+ // conformance with the C++ standard.
if ((LCanPointeeTy->isFunctionType() || RCanPointeeTy->isFunctionType())
&& !LHSIsNull && !RHSIsNull) {
- Diag(Loc, diag::ext_typecheck_comparison_of_fptr_to_void)
+ Diag(Loc,
+ isSFINAEContext()?
+ diag::err_typecheck_comparison_of_fptr_to_void
+ : diag::ext_typecheck_comparison_of_fptr_to_void)
<< lType << rType << lex->getSourceRange() << rex->getSourceRange();
+
+ if (isSFINAEContext())
+ return QualType();
+
ImpCastExprToType(rex, lType, CastExpr::CK_BitCast);
return ResultTy;
}
@@ -5591,40 +5599,36 @@
return ResultTy;
}
}
- if (lType->isAnyPointerType() && rType->isIntegerType()) {
+ if ((lType->isAnyPointerType() && rType->isIntegerType()) ||
+ (lType->isIntegerType() && rType->isAnyPointerType())) {
unsigned DiagID = 0;
- if (RHSIsNull) {
- if (isRelational)
+ bool isError = false;
+ if ((LHSIsNull && lType->isIntegerType()) ||
+ (RHSIsNull && rType->isIntegerType())) {
+ if (isRelational && !getLangOptions().CPlusPlus)
DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_and_zero;
- } else if (isRelational)
+ } else if (isRelational && !getLangOptions().CPlusPlus)
DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_integer;
- else
+ else if (getLangOptions().CPlusPlus) {
+ DiagID = diag::err_typecheck_comparison_of_pointer_integer;
+ isError = true;
+ } else
DiagID = diag::ext_typecheck_comparison_of_pointer_integer;
if (DiagID) {
Diag(Loc, DiagID)
<< lType << rType << lex->getSourceRange() << rex->getSourceRange();
+ if (isError)
+ return QualType();
}
- ImpCastExprToType(rex, lType, CastExpr::CK_IntegralToPointer);
- return ResultTy;
- }
- if (lType->isIntegerType() && rType->isAnyPointerType()) {
- unsigned DiagID = 0;
- if (LHSIsNull) {
- if (isRelational)
- DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_and_zero;
- } else if (isRelational)
- DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_integer;
+
+ if (lType->isIntegerType())
+ ImpCastExprToType(lex, rType, CastExpr::CK_IntegralToPointer);
else
- DiagID = diag::ext_typecheck_comparison_of_pointer_integer;
-
- if (DiagID) {
- Diag(Loc, DiagID)
- << lType << rType << lex->getSourceRange() << rex->getSourceRange();
- }
- ImpCastExprToType(lex, rType, CastExpr::CK_IntegralToPointer);
+ ImpCastExprToType(rex, lType, CastExpr::CK_IntegralToPointer);
return ResultTy;
}
+
// Handle block pointers.
if (!isRelational && RHSIsNull
&& lType->isBlockPointerType() && rType->isIntegerType()) {
diff --git a/test/SemaCXX/compare.cpp b/test/SemaCXX/compare.cpp
index 4790347..ebecc06 100644
--- a/test/SemaCXX/compare.cpp
+++ b/test/SemaCXX/compare.cpp
@@ -198,3 +198,11 @@
enum en { zero };
return i > zero;
}
+
+enum E { e };
+void test2(int i, void *vp) {
+ if (test1 == vp) { } // expected-warning{{equality comparison between function pointer and void pointer}}
+ if (test1 == e) { } // expected-error{{comparison between pointer and integer}}
+ if (vp < 0) { }
+ if (test1 < e) { } // expected-error{{comparison between pointer and integer}}
+}