// RUN: %clang_cc1 -std=c++20 -fsyntax-only -verify=ref %s // RUN: %clang_cc1 -std=c++20 -fsyntax-only -fexperimental-new-constant-interpreter -verify %s /// This is a version of the nqueens.cpp from SemaCXX/, /// but we don't initialize the State variable in the /// Board constructors. /// This tests that InterpFrame::describe(). typedef unsigned long uint64_t; struct Board { uint64_t State; bool Failed; constexpr Board() : Failed(false) {} constexpr Board(const Board &O) : Failed(O.Failed) {} constexpr Board(uint64_t State, bool Failed = false) : Failed(Failed) {} constexpr Board addQueen(int Row, int Col) const { return Board(State | ((uint64_t)Row << (Col * 4))); // ref-note {{read of uninitialized object}} \ // expected-note {{read of uninitialized object}} } constexpr int getQueenRow(int Col) const { return (State >> (Col * 4)) & 0xf; } constexpr bool ok(int Row, int Col) const { return okRecurse(Row, Col, 0); } constexpr bool okRecurse(int Row, int Col, int CheckCol) const { return Col == CheckCol ? true : getQueenRow(CheckCol) == Row ? false : getQueenRow(CheckCol) == Row + (Col - CheckCol) ? false : getQueenRow(CheckCol) == Row + (CheckCol - Col) ? false : okRecurse(Row, Col, CheckCol + 1); } constexpr bool at(int Row, int Col) const { return getQueenRow(Col) == Row; } constexpr bool check(const char *, int=0, int=0) const; }; constexpr Board buildBoardRecurse(int N, int Col, const Board &B); constexpr Board buildBoardScan(int N, int Col, int Row, const Board &B); constexpr Board tryBoard(const Board &Try, int N, int Col, int Row, const Board &B) { return Try.Failed ? buildBoardScan(N, Col, Row, B) : Try; } constexpr Board buildBoardScan(int N, int Col, int Row, const Board &B) { return Row == N ? Board(0, true) : B.ok(Row, Col) ? tryBoard(buildBoardRecurse(N, Col + 1, B.addQueen(Row, Col)), // ref-note {{in call to 'B.addQueen(0, 0)}} \ // expected-note {{in call to '&Board()->addQueen(0, 0)}} N, Col, Row+1, B) : buildBoardScan(N, Col, Row + 1, B); } constexpr Board buildBoardRecurse(int N, int Col, const Board &B) { return Col == N ? B : buildBoardScan(N, Col, 0, B); // ref-note {{in call to 'buildBoardScan(8, 0, 0, Board())'}} \ // expected-note {{in call to 'buildBoardScan(8, 0, 0, Board())'}} } constexpr Board buildBoard(int N) { return buildBoardRecurse(N, 0, Board()); // ref-note {{in call to 'buildBoardRecurse(8, 0, Board())'}} \ // expected-note {{in call to 'buildBoardRecurse(8, 0, Board())'}} } constexpr Board q8 = buildBoard(8); // ref-error {{must be initialized by a constant expression}} \ // ref-note {{in call to 'buildBoard(8)'}} \ // expected-error {{must be initialized by a constant expression}} \ // expected-note {{in call to 'buildBoard(8)'}}