================ @@ -1472,3 +1472,25 @@ template<typename T> struct Outer { }; }; Outer<int>::Inner outerinner; + +void aggregate() { + struct B { + [[clang::explicit_init]] int f1; + }; + + struct S : B { // expected-warning {{uninitialized}} + int f2; + int f3 [[clang::explicit_init]]; + }; + +#if __cplusplus >= 202002L + S a({}, 0); // expected-warning {{'f1' is left uninitialized}} expected-warning {{'f3' is left uninitialized}} +#endif + S b{.f3 = 1}; // expected-warning {{'f1' is left uninitialized}} + S c{.f2 = 5}; // expected-warning {{'f1' is left uninitialized}} expected-warning {{'f3' is left uninitialized}} expected-warning {{'f3' is left uninitialized}} + c = {{}, 0}; // expected-warning {{'f1' is left uninitialized}} expected-warning {{'f3' is left uninitialized}} + S d; // expected-warning {{uninitialized}} expected-note {{constructor}} ---------------- ilya-biryukov wrote:
Okay, fair point, and I agree. I still feel that using this consistently in C++17 would be a challenge, but people are also free to disable this warning in C++17 **or** if they like multi-line initialization in C++20. To give the discussions a more useful spin: I suspect we could remove some of these warnings if we are willing to pay for a more advanced analysis in Clang. It's technically possible to check that those fields of a struct are initialized before being read in certain scenarios. The most obvious one is when all initializations are inside a single function. Currently, we would warn when the struct is created, but with the more advanced analysis we may remove this restriction in "obviously safe" cases, which is a strict improvement. https://github.com/llvm/llvm-project/pull/102040 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits