Fixed Sema::CheckEqualityOperands() and Sema::CheckRelationalOperands() to deal more
thoughtfully with incompatible pointers. This includes:
- Emit a diagnostic when two pointers aren't compatible!
- Promote one of the pointers/integers so we maintain the invariant expected by the
code generator (i.e. that the left/right types match).
- Upgrade the pointer/integer comparison diagnostic to include the types.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@41127 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/Sema/SemaExpr.cpp b/Sema/SemaExpr.cpp
index f69867f..43e0686 100644
--- a/Sema/SemaExpr.cpp
+++ b/Sema/SemaExpr.cpp
@@ -1047,22 +1047,34 @@
if (lType->isRealType() && rType->isRealType())
return Context.IntTy;
- if (lType->isPointerType()) {
- if (rType->isPointerType())
- return Context.IntTy;
- if (rType->isIntegerType()) {
- if (!rex->isNullPointerConstant(Context))
- Diag(loc, diag::ext_typecheck_comparison_of_pointer_integer,
- lex->getSourceRange(), rex->getSourceRange());
- return Context.IntTy; // the previous diagnostic is a GCC extension.
+ // All of the following pointer related warnings are GCC extensions. One
+ // day, we can consider making them errors (when -pedantic-errors is enabled).
+ if (lType->isPointerType() && rType->isPointerType()) {
+ if (!Type::pointerTypesAreCompatible(lType, rType)) {
+ Diag(loc, diag::ext_typecheck_comparison_of_distinct_pointers,
+ lType.getAsString(), rType.getAsString(),
+ lex->getSourceRange(), rex->getSourceRange());
+ promoteExprToType(rex, lType); // promote the pointer to pointer
}
- } else if (rType->isPointerType()) {
- if (lType->isIntegerType()) {
- if (!lex->isNullPointerConstant(Context))
- Diag(loc, diag::ext_typecheck_comparison_of_pointer_integer,
- lex->getSourceRange(), rex->getSourceRange());
- return Context.IntTy; // the previous diagnostic is a GCC extension.
+ return Context.IntTy;
+ }
+ if (lType->isPointerType() && rType->isIntegerType()) {
+ if (!rex->isNullPointerConstant(Context)) {
+ Diag(loc, diag::ext_typecheck_comparison_of_pointer_integer,
+ lType.getAsString(), rType.getAsString(),
+ lex->getSourceRange(), rex->getSourceRange());
+ promoteExprToType(rex, lType); // promote the integer to pointer
}
+ return Context.IntTy;
+ }
+ if (lType->isIntegerType() && rType->isPointerType()) {
+ if (!lex->isNullPointerConstant(Context)) {
+ Diag(loc, diag::ext_typecheck_comparison_of_pointer_integer,
+ lType.getAsString(), rType.getAsString(),
+ lex->getSourceRange(), rex->getSourceRange());
+ promoteExprToType(lex, rType); // promote the integer to pointer
+ }
+ return Context.IntTy;
}
InvalidOperands(loc, lex, rex);
return QualType();
@@ -1084,22 +1096,34 @@
if (lType->isArithmeticType() && rType->isArithmeticType())
return Context.IntTy;
- if (lType->isPointerType()) {
- if (rType->isPointerType())
- return Context.IntTy;
- if (rType->isIntegerType()) {
- if (!rex->isNullPointerConstant(Context))
- Diag(loc, diag::ext_typecheck_comparison_of_pointer_integer,
- lex->getSourceRange(), rex->getSourceRange());
- return Context.IntTy; // the previous diagnostic is a GCC extension.
+ // All of the following pointer related warnings are GCC extensions. One
+ // day, we can consider making them errors (when -pedantic-errors is enabled).
+ if (lType->isPointerType() && rType->isPointerType()) {
+ if (!Type::pointerTypesAreCompatible(lType, rType)) {
+ Diag(loc, diag::ext_typecheck_comparison_of_distinct_pointers,
+ lType.getAsString(), rType.getAsString(),
+ lex->getSourceRange(), rex->getSourceRange());
+ promoteExprToType(rex, lType); // promote the pointer to pointer
}
- } else if (rType->isPointerType()) {
- if (lType->isIntegerType()) {
- if (!lex->isNullPointerConstant(Context))
- Diag(loc, diag::ext_typecheck_comparison_of_pointer_integer,
- lex->getSourceRange(), rex->getSourceRange());
- return Context.IntTy; // the previous diagnostic is a GCC extension.
+ return Context.IntTy;
+ }
+ if (lType->isPointerType() && rType->isIntegerType()) {
+ if (!rex->isNullPointerConstant(Context)) {
+ Diag(loc, diag::ext_typecheck_comparison_of_pointer_integer,
+ lType.getAsString(), rType.getAsString(),
+ lex->getSourceRange(), rex->getSourceRange());
+ promoteExprToType(rex, lType); // promote the integer to pointer
}
+ return Context.IntTy;
+ }
+ if (lType->isIntegerType() && rType->isPointerType()) {
+ if (!lex->isNullPointerConstant(Context)) {
+ Diag(loc, diag::ext_typecheck_comparison_of_pointer_integer,
+ lType.getAsString(), rType.getAsString(),
+ lex->getSourceRange(), rex->getSourceRange());
+ promoteExprToType(lex, rType); // promote the integer to pointer
+ }
+ return Context.IntTy;
}
InvalidOperands(loc, lex, rex);
return QualType();
diff --git a/include/clang/Basic/DiagnosticKinds.def b/include/clang/Basic/DiagnosticKinds.def
index 9137a84..e13a95b 100644
--- a/include/clang/Basic/DiagnosticKinds.def
+++ b/include/clang/Basic/DiagnosticKinds.def
@@ -611,7 +611,9 @@
DIAG(err_typecheck_invalid_operands, ERROR,
"invalid operands to binary expression ('%0' and '%1')")
DIAG(ext_typecheck_comparison_of_pointer_integer, WARNING,
- "comparison between pointer and integer")
+ "comparison between pointer and integer ('%0' and '%1')")
+DIAG(ext_typecheck_comparison_of_distinct_pointers, WARNING,
+ "comparison of distinct pointer types ('%0' and '%1')")
DIAG(err_typecheck_assign_const, ERROR,
"read-only variable is not assignable")
DIAG(err_typecheck_assign_incompatible, ERROR,
diff --git a/test/Parser/pointer_promotion.c b/test/Parser/pointer_promotion.c
new file mode 100644
index 0000000..18cd968
--- /dev/null
+++ b/test/Parser/pointer_promotion.c
@@ -0,0 +1,18 @@
+// RUN: clang -parse-ast-check %s
+
+int test() {
+ void *vp;
+ int *ip;
+ char *cp;
+ struct foo *fp;
+ struct bar *bp;
+ short sint = 7;
+
+ if (ip < cp) ; // expected-warning {{comparison of distinct pointer types ('int *' and 'char *')}}
+ if (cp < fp) ; // expected-warning {{comparison of distinct pointer types ('char *' and 'struct foo *')}}
+ if (fp < bp) ; // expected-warning {{comparison of distinct pointer types ('struct foo *' and 'struct bar *')}}
+ if (ip < 7) ; // expected-warning {{comparison between pointer and integer ('int *' and 'int')}}
+ if (sint < ip) ; // expected-warning {{comparison between pointer and integer ('int' and 'int *')}}
+ if (ip == cp) ; // expected-warning {{comparison of distinct pointer types ('int *' and 'char *')}}
+}
+