From: Artyom Skrobov Date: Fri, 27 Dec 2013 16:29:53 +0000 Subject: [PATCH] Warn when NULL is returned from 'operator new' without 'throw()' --- include/clang/Basic/DiagnosticGroups.td | 1 + include/clang/Basic/DiagnosticSemaKinds.td | 3 +++ lib/Sema/SemaStmt.cpp | 14 ++++++++++++++ test/SemaCXX/new-delete.cpp | 2 +- test/SemaCXX/warn-new-overaligned.cpp | 4 ++-- 5 files changed, 21 insertions(+), 3 deletions(-) diff --git a/include/clang/Basic/DiagnosticGroups.td b/include/clang/Basic/DiagnosticGroups.td index bf77259..e1320be 100644 --- a/include/clang/Basic/DiagnosticGroups.td +++ b/include/clang/Basic/DiagnosticGroups.td @@ -226,6 +226,7 @@ def : DiagGroup<"overflow">; def ForwardClassReceiver : DiagGroup<"receiver-forward-class">; def MethodAccess : DiagGroup<"objc-method-access">; def ObjCReceiver : DiagGroup<"receiver-expr">; +def OperatorNewReturnsNull : DiagGroup<"new-returns-null">; def OverlengthStrings : DiagGroup<"overlength-strings">; def OverloadedVirtual : DiagGroup<"overloaded-virtual">; def PrivateExtern : DiagGroup<"private-extern">; diff --git a/include/clang/Basic/DiagnosticSemaKinds.td b/include/clang/Basic/DiagnosticSemaKinds.td index 3a3c93d..9825759 100644 --- a/include/clang/Basic/DiagnosticSemaKinds.td +++ b/include/clang/Basic/DiagnosticSemaKinds.td @@ -6003,6 +6003,9 @@ def err_operator_new_delete_too_few_parameters : Error< "%0 must have at least one parameter">; def err_operator_new_delete_template_too_few_parameters : Error< "%0 template must have at least two parameters">; +def warn_operator_new_returns_null : Warning< + "%0 must not return NULL unless it is declared 'throw()'">, + InGroup; def err_operator_new_dependent_param_type : Error< "%0 cannot take a dependent type as first parameter; " diff --git a/lib/Sema/SemaStmt.cpp b/lib/Sema/SemaStmt.cpp index e4fe9c3..27a834d 100644 --- a/lib/Sema/SemaStmt.cpp +++ b/lib/Sema/SemaStmt.cpp @@ -2779,6 +2779,20 @@ Sema::ActOnReturnStmt(SourceLocation ReturnLoc, Expr *RetValExp) { if (FD->isNoReturn()) Diag(ReturnLoc, diag::warn_noreturn_function_has_return_expr) << FD->getDeclName(); + + OverloadedOperatorKind Op = FD->getOverloadedOperator(); + if (Op == OO_New || Op == OO_Array_New) { + const FunctionProtoType *Proto + = FD->getTypeSourceInfo()->getType()->castAs(); + llvm::APSInt ReturnValue; + + if (!Proto->isNothrow(Context) && + RetValExp->EvaluateAsInt(ReturnValue, Context, + Expr::SE_AllowSideEffects) && + ReturnValue == 0) + Diag(ReturnLoc, diag::warn_operator_new_returns_null) + << FD->getDeclName(); + } } else if (ObjCMethodDecl *MD = getCurMethodDecl()) { FnRetType = MD->getResultType(); if (MD->hasRelatedResultType() && MD->getClassInterface()) { diff --git a/test/SemaCXX/new-delete.cpp b/test/SemaCXX/new-delete.cpp index 7facd10..59e2574 100644 --- a/test/SemaCXX/new-delete.cpp +++ b/test/SemaCXX/new-delete.cpp @@ -1,4 +1,4 @@ -// RUN: %clang_cc1 -fsyntax-only -verify %s -triple=i686-pc-linux-gnu +// RUN: %clang_cc1 -fsyntax-only -verify %s -triple=i686-pc-linux-gnu -Wno-new-returns-null #include diff --git a/test/SemaCXX/warn-new-overaligned.cpp b/test/SemaCXX/warn-new-overaligned.cpp index 42a4e35..ce08cf0 100644 --- a/test/SemaCXX/warn-new-overaligned.cpp +++ b/test/SemaCXX/warn-new-overaligned.cpp @@ -38,7 +38,7 @@ struct Test { } __attribute__((aligned(256))); void* operator new(unsigned long) { - return 0; + return 0; // expected-warning {{'operator new' must not return NULL unless it is declared 'throw()'}} } SeparateCacheLines high_contention_data[10]; @@ -59,7 +59,7 @@ struct Test { } __attribute__((aligned(256))); void* operator new[](unsigned long) { - return 0; + return 0; // expected-warning {{'operator new[]' must not return NULL unless it is declared 'throw()'}} } SeparateCacheLines high_contention_data[10]; -- 1.7.9.5