5ac3435818
The -Wunsafe-buffer-usage warning should fire on any call to a function annotated with [[clang::unsafe_buffer_usage]], however it omitted calls to constructors, since the expression is a CXXConstructExpr which does not subclass CallExpr. Thus the matcher on callExpr() does not find these expressions. Add a new WarningGadget that matches cxxConstructExpr that are calling a CXXConstructDecl annotated by [[clang::unsafe_buffer_usage]] and fires the warning. The new UnsafeBufferUsageCtorAttrGadget gadget explicitly avoids matching against the std::span(ptr, size) constructor because that is handled by SpanTwoParamConstructorGadget and we never want two gadgets to match the same thing (and this is guarded by asserts). The gadgets themselves do not report the warnings, instead each gadget's Stmt is passed to the UnsafeBufferUsageHandler (implemented by UnsafeBufferUsageReporter). The Reporter is previously hardcoded that a CXXConstructExpr statement must be a match for std::span(ptr, size), but that is no longer the case. We want the Reporter to generate different warnings (in the -Wunsafe-buffer-usage-in-container subgroup) for the span contructor. And we will want it to report more warnings for other std-container-specific gadgets in the future. To handle this we allow the gadget to control if the warning is general (it calls handleUnsafeBufferUsage()) or is a std-container-specific warning (it calls handleUnsafeOperationInContainer()). Then the WarningGadget grows a virtual method to dispatch to the appropriate path in the UnsafeBufferUsageHandler. By doing so, we no longer need getBaseStmt in the Gadget interface. The only use of it for FixableGadgets was to get the SourceLocation, so we make an explicit virtual method for that on Gadget. Then the handleUnsafeOperation() dispatcher can be a virtual method that is only in WarningGadget. The SpanTwoParamConstructorGadget gadget dispatches to handleUnsafeOperationInContainer() while the other WarningGadgets all dispatch to the original handleUnsafeBufferUsage(). Tests are added for annotated constructors, conversion operattors, call operators, fold expressions, and regular methods. Issue #80482
122 KiB
122 KiB