diff options
Diffstat (limited to 'clang/test/Sema')
| -rw-r--r-- | clang/test/Sema/warn-lifetime-safety.cpp | 138 |
1 files changed, 100 insertions, 38 deletions
diff --git a/clang/test/Sema/warn-lifetime-safety.cpp b/clang/test/Sema/warn-lifetime-safety.cpp index f6bec6e..4f234f0 100644 --- a/clang/test/Sema/warn-lifetime-safety.cpp +++ b/clang/test/Sema/warn-lifetime-safety.cpp @@ -126,11 +126,15 @@ void definite_single_pointer_multiple_loans_gsl(bool cond) { v.use(); // expected-note 2 {{later used here}} } - -//===----------------------------------------------------------------------===// -// Potential (Maybe) Use-After-Free (-W...strict) -// These are cases where the pointer *may* become dangling, depending on the path taken. -//===----------------------------------------------------------------------===// +void definite_if_branch(bool cond) { + MyObj safe; + MyObj* p = &safe; + if (cond) { + MyObj temp; + p = &temp; // expected-warning {{object whose reference is captured does not live long enough}} + } // expected-note {{destroyed here}} + (void)*p; // expected-note {{later used here}} +} void potential_if_branch(bool cond) { MyObj safe; @@ -139,15 +143,18 @@ void potential_if_branch(bool cond) { MyObj temp; p = &temp; // expected-warning {{object whose reference is captured may not live long enough}} } // expected-note {{destroyed here}} - (void)*p; // expected-note {{later used here}} + if (!cond) + (void)*p; // expected-note {{later used here}} + else + p = &safe; } -void potential_if_branch_gsl(bool cond) { +void definite_if_branch_gsl(bool cond) { MyObj safe; View v = safe; if (cond) { MyObj temp; - v = temp; // expected-warning {{object whose reference is captured may not live long enough}} + v = temp; // expected-warning {{object whose reference is captured does not live long enough}} } // expected-note {{destroyed here}} v.use(); // expected-note {{later used here}} } @@ -159,13 +166,14 @@ void definite_potential_together(bool cond) { { MyObj s; - p_definite = &s; // expected-warning {{does not live long enough}} - if (cond) { - p_maybe = &s; // expected-warning {{may not live long enough}} - } - } // expected-note 2 {{destroyed here}} - (void)*p_definite; // expected-note {{later used here}} - (void)*p_maybe; // expected-note {{later used here}} + if (cond) + p_definite = &s; // expected-warning {{does not live long enough}} + if (cond) + p_maybe = &s; // expected-warning {{may not live long enough}} + } // expected-note 2 {{destroyed here}} + (void)*p_definite; // expected-note {{later used here}} + if (!cond) + (void)*p_maybe; // expected-note {{later used here}} } void definite_overrides_potential(bool cond) { @@ -189,10 +197,19 @@ void definite_overrides_potential(bool cond) { (void)*q; } - -//===----------------------------------------------------------------------===// -// Control Flow Tests -//===----------------------------------------------------------------------===// +void potential_due_to_conditional_killing(bool cond) { + MyObj safe; + MyObj* q; + { + MyObj s; + q = &s; // expected-warning {{may not live long enough}} + } // expected-note {{destroyed here}} + if (cond) { + // 'q' is conditionally "rescued". 'p' is not. + q = &safe; + } + (void)*q; // expected-note {{later used here}} +} void potential_for_loop_use_after_loop_body(MyObj safe) { MyObj* p = &safe; @@ -215,34 +232,35 @@ void potential_for_loop_gsl() { void potential_for_loop_use_before_loop_body(MyObj safe) { MyObj* p = &safe; + // Prefer the earlier use for diagnsotics. for (int i = 0; i < 1; ++i) { (void)*p; // expected-note {{later used here}} MyObj s; - p = &s; // expected-warning {{may not live long enough}} + p = &s; // expected-warning {{does not live long enough}} } // expected-note {{destroyed here}} (void)*p; } -void potential_loop_with_break(bool cond) { +void definite_loop_with_break(bool cond) { MyObj safe; MyObj* p = &safe; for (int i = 0; i < 10; ++i) { if (cond) { MyObj temp; - p = &temp; // expected-warning {{may not live long enough}} + p = &temp; // expected-warning {{does not live long enough}} break; // expected-note {{destroyed here}} } } (void)*p; // expected-note {{later used here}} } -void potential_loop_with_break_gsl(bool cond) { +void definite_loop_with_break_gsl(bool cond) { MyObj safe; View v = safe; for (int i = 0; i < 10; ++i) { if (cond) { MyObj temp; - v = temp; // expected-warning {{object whose reference is captured may not live long enough}} + v = temp; // expected-warning {{object whose reference is captured does not live long enough}} break; // expected-note {{destroyed here}} } } @@ -250,37 +268,52 @@ void potential_loop_with_break_gsl(bool cond) { } void potential_multiple_expiry_of_same_loan(bool cond) { - // Choose the last expiry location for the loan. + // Choose the last expiry location for the loan (e.g., through scope-ends and break statements). MyObj safe; MyObj* p = &safe; for (int i = 0; i < 10; ++i) { MyObj unsafe; if (cond) { - p = &unsafe; // expected-warning {{may not live long enough}} - break; + p = &unsafe; // expected-warning {{does not live long enough}} + break; // expected-note {{destroyed here}} } - } // expected-note {{destroyed here}} + } (void)*p; // expected-note {{later used here}} p = &safe; for (int i = 0; i < 10; ++i) { MyObj unsafe; if (cond) { - p = &unsafe; // expected-warning {{may not live long enough}} + p = &unsafe; // expected-warning {{does not live long enough}} if (cond) - break; + break; // expected-note {{destroyed here}} } - } // expected-note {{destroyed here}} + } (void)*p; // expected-note {{later used here}} p = &safe; for (int i = 0; i < 10; ++i) { if (cond) { MyObj unsafe2; - p = &unsafe2; // expected-warning {{may not live long enough}} + p = &unsafe2; // expected-warning {{does not live long enough}} break; // expected-note {{destroyed here}} } } + + // TODO: This can be argued to be a "maybe" warning. This is because + // we only check for confidence of liveness and not the confidence of + // the loan contained in an origin. To deal with this, we can introduce + // a confidence in loan propagation analysis as well like liveness. + (void)*p; // expected-note {{later used here}} + + p = &safe; + for (int i = 0; i < 10; ++i) { + MyObj unsafe; + if (cond) + p = &unsafe; // expected-warning {{does not live long enough}} + if (cond) + break; // expected-note {{destroyed here}} + } (void)*p; // expected-note {{later used here}} } @@ -298,13 +331,14 @@ void potential_switch(int mode) { break; } } - (void)*p; // expected-note {{later used here}} + if (mode == 2) + (void)*p; // expected-note {{later used here}} } void definite_switch(int mode) { MyObj safe; MyObj* p = &safe; - // All cases are UaF --> Definite error. + // A use domintates all the loan expires --> all definite error. switch (mode) { case 1: { MyObj temp1; @@ -347,6 +381,21 @@ void definite_switch_gsl(int mode) { v.use(); // expected-note 3 {{later used here}} } +void loan_from_previous_iteration(MyObj safe, bool condition) { + MyObj* p = &safe; + MyObj* q = &safe; + + while (condition) { + MyObj x; + p = &x; // expected-warning {{may not live long enough}} + + if (condition) + q = p; + (void)*p; + (void)*q; // expected-note {{later used here}} + } // expected-note {{destroyed here}} +} + //===----------------------------------------------------------------------===// // No-Error Cases //===----------------------------------------------------------------------===// @@ -372,6 +421,19 @@ void no_error_if_dangle_then_rescue_gsl() { v.use(); // This is safe. } +void no_error_loan_from_current_iteration(bool cond) { + // See https://github.com/llvm/llvm-project/issues/156959. + MyObj b; + while (cond) { + MyObj a; + View p = b; + if (cond) { + p = a; + } + (void)p; + } +} + //===----------------------------------------------------------------------===// // Lifetimebound Attribute Tests @@ -415,9 +477,9 @@ void lifetimebound_multiple_args_potential(bool cond) { MyObj obj1; if (cond) { MyObj obj2; - v = Choose(true, - obj1, // expected-warning {{object whose reference is captured may not live long enough}} - obj2); // expected-warning {{object whose reference is captured may not live long enough}} + v = Choose(true, + obj1, // expected-warning {{object whose reference is captured does not live long enough}} + obj2); // expected-warning {{object whose reference is captured does not live long enough}} } // expected-note {{destroyed here}} } // expected-note {{destroyed here}} v.use(); // expected-note 2 {{later used here}} @@ -488,7 +550,7 @@ void lifetimebound_partial_safety(bool cond) { MyObj temp_obj; v = Choose(true, safe_obj, - temp_obj); // expected-warning {{object whose reference is captured may not live long enough}} + temp_obj); // expected-warning {{object whose reference is captured does not live long enough}} } // expected-note {{destroyed here}} v.use(); // expected-note {{later used here}} } |