Fix a false-positive with cert-err58-cpp.

If a variable is declared constexpr then its initializer needs to be a constant expression, and thus, cannot throw. This check is about not throwing exceptions before main() runs, and so it doesn't apply if the initializer cannot throw. This silences the diagnostic when initializing a constexpr variable and fixes PR35457.

llvm-svn: 347745
This commit is contained in:
Aaron Ballman 2018-11-28 11:57:13 +00:00
parent af860d44fe
commit dda6290f16
2 changed files with 15 additions and 2 deletions

View File

@ -26,7 +26,7 @@ void StaticObjectExceptionCheck::registerMatchers(MatchFinder *Finder) {
// initializer that can throw.
Finder->addMatcher(
varDecl(anyOf(hasThreadStorageDuration(), hasStaticStorageDuration()),
unless(hasAncestor(functionDecl())),
unless(anyOf(isConstexpr(), hasAncestor(functionDecl()))),
anyOf(hasDescendant(cxxConstructExpr(hasDeclaration(
cxxConstructorDecl(unless(isNoThrow())).bind("func")))),
hasDescendant(cxxNewExpr(hasDeclaration(

View File

@ -1,7 +1,7 @@
// RUN: clang-tidy %s -checks="-*,cert-err58-cpp" -- -std=c++11 -target x86_64-pc-linux-gnu \
// RUN: | FileCheck %s -check-prefix=CHECK-EXCEPTIONS \
// RUN: -implicit-check-not="{{warning|error}}:"
// RUN: clang-tidy %s -checks="-*,cert-err58-cpp" -- -fno-exceptions -std=c++11 -target x86_64-pc-linux-gnu \
// RUN: clang-tidy %s -checks="-*,cert-err58-cpp" -- -DNONEXCEPTIONS -fno-exceptions -std=c++11 -target x86_64-pc-linux-gnu \
// RUN: | FileCheck %s -allow-empty -check-prefix=CHECK-NONEXCEPTIONS \
// RUN: -implicit-check-not="{{warning|error}}:"
@ -223,3 +223,16 @@ W Statics::w;
// CHECK-EXCEPTIONS: :[[@LINE-1]]:12: warning: initialization of 'w' with static storage duration may throw an exception that cannot be caught
// CHECK-EXCEPTIONS: 29:3: note: possibly throwing constructor declared here
// CHECK-NONEXCEPTIONS-NOT: warning:
#ifndef NONEXCEPTIONS
namespace pr35457 {
constexpr int foo(int x) { if (x <= 0) throw 12; return x; }
constexpr int bar = foo(1); // OK
// CHECK-EXCEPTIONS-NOT: warning: initialization of 'bar' with static storage
int baz = foo(0); // Not OK; throws at runtime when exceptions are enabled.
// CHECK-EXCEPTIONS: :[[@LINE-1]]:5: warning: initialization of 'baz' with static storage duration may throw an exception that cannot be caught [cert-err58-cpp]
// CHECK-EXCEPTIONS: :[[@LINE-6]]:15: note: possibly throwing function declared here
} // namespace pr35457
#endif // NONEXCEPTIONS