diff options
| -rw-r--r-- | clang/include/clang/Basic/DiagnosticSemaKinds.td | 5 | ||||
| -rw-r--r-- | clang/lib/Sema/SemaChecking.cpp | 4 | ||||
| -rw-r--r-- | clang/test/Sema/warn-alloca.c | 20 |
3 files changed, 29 insertions, 0 deletions
diff --git a/clang/include/clang/Basic/DiagnosticSemaKinds.td b/clang/include/clang/Basic/DiagnosticSemaKinds.td index e58a0b16bd6..d5e3b767e96 100644 --- a/clang/include/clang/Basic/DiagnosticSemaKinds.td +++ b/clang/include/clang/Basic/DiagnosticSemaKinds.td @@ -2779,6 +2779,11 @@ def err_no_accessor_for_property : Error< def err_cannot_find_suitable_accessor : Error< "cannot find suitable %select{getter|setter}0 for property %1">; +def warn_alloca : Warning< + "use of function %0 is discouraged; there is no way to check for failure but " + "failure may still occur, resulting in a possibly exploitable security vulnerability">, + InGroup<DiagGroup<"alloca">>, DefaultIgnore; + def warn_alloca_align_alignof : Warning< "second argument to __builtin_alloca_with_align is supposed to be in bits">, InGroup<DiagGroup<"alloca-with-align-alignof">>; diff --git a/clang/lib/Sema/SemaChecking.cpp b/clang/lib/Sema/SemaChecking.cpp index f9f82cdeef4..436e17a0e39 100644 --- a/clang/lib/Sema/SemaChecking.cpp +++ b/clang/lib/Sema/SemaChecking.cpp @@ -1179,6 +1179,10 @@ Sema::CheckBuiltinFunctionCall(FunctionDecl *FDecl, unsigned BuiltinID, case Builtin::BI__builtin_alloca_with_align: if (SemaBuiltinAllocaWithAlign(TheCall)) return ExprError(); + LLVM_FALLTHROUGH; + case Builtin::BI__builtin_alloca: + Diag(TheCall->getBeginLoc(), diag::warn_alloca) + << TheCall->getDirectCallee(); break; case Builtin::BI__assume: case Builtin::BI__builtin_assume: diff --git a/clang/test/Sema/warn-alloca.c b/clang/test/Sema/warn-alloca.c new file mode 100644 index 00000000000..0990e11ef2f --- /dev/null +++ b/clang/test/Sema/warn-alloca.c @@ -0,0 +1,20 @@ +// RUN: %clang_cc1 -DSILENCE -fsyntax-only -verify -Wall %s +// RUN: %clang_cc1 -fsyntax-only -verify -Walloca %s + +#ifdef SILENCE + // expected-no-diagnostics +#endif + +void test1(int a) { + __builtin_alloca(a); +#ifndef SILENCE + // expected-warning@-2 {{use of function '__builtin_alloca' is discouraged; there is no way to check for failure but failure may still occur, resulting in a possibly exploitable security vulnerability}} +#endif +} + +void test2(int a) { + __builtin_alloca_with_align(a, 32); +#ifndef SILENCE + // expected-warning@-2 {{use of function '__builtin_alloca_with_align' is discouraged; there is no way to check for failure but failure may still occur, resulting in a possibly exploitable security vulnerability}} +#endif +} |
