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6502-c++ 11.1.0
ARM gcc 10.2 (linux)
ARM gcc 10.2.1 (none)
ARM gcc 10.3 (linux)
ARM gcc 10.3.1 (2021.07 none)
ARM gcc 10.3.1 (2021.10 none)
ARM gcc 11.1 (linux)
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ARM gcc 8.2 (WinCE)
ARM gcc 8.2 (linux)
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ARM gcc 8.5 (linux)
ARM gcc 9.2.1 (none)
ARM gcc 9.3 (linux)
ARM gcc trunk (linux)
ARM msvc v19.0 (WINE)
ARM msvc v19.10 (WINE)
ARM msvc v19.14 (WINE)
ARM64 gcc 10.2
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ARM64 msvc v19.14 (WINE)
AVR gcc 10.3.0
AVR gcc 11.1.0
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AVR gcc 9.2.0
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FRC 2019
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KVX gcc 7.5 (ACB 4.1.0)
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MSP430 gcc 6.2.1
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RISC-V rv32gc clang 10.0.0
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RISC-V rv32gc clang 11.0.0
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RISC-V rv32gc clang 12.0.0
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RISC-V rv32gc gcc 10.2.0
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RISC-V rv32gc gcc 11.2.0
RISC-V rv32gc gcc 11.3.0
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RISC-V rv32gc gcc 8.2.0
RISC-V rv32gc gcc 8.5.0
RISC-V rv32gc gcc 9.4.0
RISC-V rv64gc clang (trunk)
RISC-V rv64gc clang 10.0.0
RISC-V rv64gc clang 10.0.1
RISC-V rv64gc clang 11.0.0
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RISC-V rv64gc clang 12.0.0
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RISC-V rv64gc clang 9.0.0
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RISC-V rv64gc gcc 10.2.0
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RISC-V rv64gc gcc 11.2.0
RISC-V rv64gc gcc 11.3.0
RISC-V rv64gc gcc 12.1.0
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RISC-V rv64gc gcc 8.5.0
RISC-V rv64gc gcc 9.4.0
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WebAssembly clang (trunk)
Xtensa ESP32 gcc 8.2.0 (2019r2)
Xtensa ESP32 gcc 8.2.0 (2020r1)
Xtensa ESP32 gcc 8.2.0 (2020r2)
Xtensa ESP32 gcc 8.4.0 (2020r3)
Xtensa ESP32 gcc 8.4.0 (2021r1)
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Xtensa ESP32-S2 gcc 8.2.0 (2019r2)
Xtensa ESP32-S2 gcc 8.2.0 (2020r1)
Xtensa ESP32-S2 gcc 8.2.0 (2020r2)
Xtensa ESP32-S2 gcc 8.4.0 (2020r3)
Xtensa ESP32-S2 gcc 8.4.0 (2021r1)
Xtensa ESP32-S2 gcc 8.4.0 (2021r2)
Xtensa ESP32-S3 gcc 8.4.0 (2020r3)
Xtensa ESP32-S3 gcc 8.4.0 (2021r1)
Xtensa ESP32-S3 gcc 8.4.0 (2021r2)
arm64 msvc v19.28 VS16.9
arm64 msvc v19.29 VS16.10
arm64 msvc v19.29 VS16.11
arm64 msvc v19.30
arm64 msvc v19.31
arm64 msvc v19.32
arm64 msvc v19.latest
armv7-a clang (trunk)
armv7-a clang 10.0.0
armv7-a clang 10.0.1
armv7-a clang 11.0.0
armv7-a clang 11.0.1
armv7-a clang 9.0.0
armv7-a clang 9.0.1
armv8-a clang (trunk)
armv8-a clang (trunk, all architectural features)
armv8-a clang 10.0.0
armv8-a clang 10.0.1
armv8-a clang 11.0.0
armv8-a clang 11.0.1
armv8-a clang 9.0.0
armv8-a clang 9.0.1
ellcc 0.1.33
ellcc 0.1.34
ellcc 2017-07-16
mips gcc 11.2.0
mips gcc 5.4
mips gcc 9.3.0
mips64 (el) gcc 5.4
mips64 gcc 11.2.0
mips64 gcc 5.4
mipsel gcc 5.4
nanoMIPS gcc 6.3.0 (mtk)
power gcc 11.2.0
power gcc 4.8.5
power64 AT12.0 (gcc8)
power64 AT13.0 (gcc9)
power64 gcc 11.2.0
power64le AT12.0 (gcc8)
power64le AT13.0 (gcc9)
power64le clang (trunk)
power64le gcc 11.2.0
power64le gcc 6.3.0
powerpc64 clang (trunk)
s390x gcc 11.2.0
x64 msvc v19.0 (WINE)
x64 msvc v19.10 (WINE)
x64 msvc v19.14
x64 msvc v19.14 (WINE)
x64 msvc v19.15
x64 msvc v19.16
x64 msvc v19.20
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x64 msvc v19.22
x64 msvc v19.23
x64 msvc v19.24
x64 msvc v19.25
x64 msvc v19.26
x64 msvc v19.27
x64 msvc v19.28
x64 msvc v19.28 VS16.9
x64 msvc v19.29 VS16.10
x64 msvc v19.29 VS16.11
x64 msvc v19.30
x64 msvc v19.31
x64 msvc v19.32
x64 msvc v19.latest
x86 djgpp 4.9.4
x86 djgpp 5.5.0
x86 djgpp 6.4.0
x86 djgpp 7.2.0
x86 msvc v19.0 (WINE)
x86 msvc v19.10 (WINE)
x86 msvc v19.14
x86 msvc v19.14 (WINE)
x86 msvc v19.15
x86 msvc v19.16
x86 msvc v19.20
x86 msvc v19.21
x86 msvc v19.22
x86 msvc v19.23
x86 msvc v19.24
x86 msvc v19.25
x86 msvc v19.26
x86 msvc v19.27
x86 msvc v19.28
x86 msvc v19.28 VS16.9
x86 msvc v19.29 VS16.10
x86 msvc v19.29 VS16.11
x86 msvc v19.30
x86 msvc v19.31
x86 msvc v19.32
x86 msvc v19.latest
x86-64 Zapcc 190308
x86-64 clang (assertions trunk)
x86-64 clang (experimental -Wlifetime)
x86-64 clang (experimental P1061)
x86-64 clang (experimental P1144)
x86-64 clang (experimental P1221)
x86-64 clang (experimental auto NSDMI)
x86-64 clang (experimental pattern matching)
x86-64 clang (old concepts branch)
x86-64 clang (reflection)
x86-64 clang (resugar)
x86-64 clang (thephd.dev)
x86-64 clang (trunk)
x86-64 clang (widberg)
x86-64 clang 10.0.0
x86-64 clang 10.0.1
x86-64 clang 11.0.0
x86-64 clang 11.0.1
x86-64 clang 12.0.0
x86-64 clang 12.0.1
x86-64 clang 13.0.0
x86-64 clang 13.0.1
x86-64 clang 14.0.0
x86-64 clang 3.0.0
x86-64 clang 3.1
x86-64 clang 3.2
x86-64 clang 3.3
x86-64 clang 3.4.1
x86-64 clang 3.5
x86-64 clang 3.5.1
x86-64 clang 3.5.2
x86-64 clang 3.6
x86-64 clang 3.7
x86-64 clang 3.7.1
x86-64 clang 3.8
x86-64 clang 3.8.1
x86-64 clang 3.9.0
x86-64 clang 3.9.1
x86-64 clang 4.0.0
x86-64 clang 4.0.1
x86-64 clang 5.0.0
x86-64 clang 5.0.1
x86-64 clang 5.0.2
x86-64 clang 6.0.0
x86-64 clang 6.0.1
x86-64 clang 7.0.0
x86-64 clang 7.0.1
x86-64 clang 7.1.0
x86-64 clang 8.0.0
x86-64 clang 8.0.1
x86-64 clang 9.0.0
x86-64 clang 9.0.1
x86-64 gcc (contract labels)
x86-64 gcc (contracts)
x86-64 gcc (coroutines)
x86-64 gcc (modules)
x86-64 gcc (trunk)
x86-64 gcc 10.1
x86-64 gcc 10.2
x86-64 gcc 10.3
x86-64 gcc 10.4
x86-64 gcc 11.1
x86-64 gcc 11.2
x86-64 gcc 11.3
x86-64 gcc 12.1
x86-64 gcc 4.1.2
x86-64 gcc 4.4.7
x86-64 gcc 4.5.3
x86-64 gcc 4.6.4
x86-64 gcc 4.7.1
x86-64 gcc 4.7.2
x86-64 gcc 4.7.3
x86-64 gcc 4.7.4
x86-64 gcc 4.8.1
x86-64 gcc 4.8.2
x86-64 gcc 4.8.3
x86-64 gcc 4.8.4
x86-64 gcc 4.8.5
x86-64 gcc 4.9.0
x86-64 gcc 4.9.1
x86-64 gcc 4.9.2
x86-64 gcc 4.9.3
x86-64 gcc 4.9.4
x86-64 gcc 5.1
x86-64 gcc 5.2
x86-64 gcc 5.3
x86-64 gcc 5.4
x86-64 gcc 5.5
x86-64 gcc 6.1
x86-64 gcc 6.2
x86-64 gcc 6.3
x86-64 gcc 6.4
x86-64 gcc 7.1
x86-64 gcc 7.2
x86-64 gcc 7.3
x86-64 gcc 7.4
x86-64 gcc 7.5
x86-64 gcc 8.1
x86-64 gcc 8.2
x86-64 gcc 8.3
x86-64 gcc 8.4
x86-64 gcc 8.5
x86-64 gcc 9.1
x86-64 gcc 9.2
x86-64 gcc 9.3
x86-64 gcc 9.4
x86-64 gcc 9.5
x86-64 icc 13.0.1
x86-64 icc 16.0.3
x86-64 icc 17.0.0
x86-64 icc 18.0.0
x86-64 icc 19.0.0
x86-64 icc 19.0.1
x86-64 icc 2021.1.2
x86-64 icc 2021.2.0
x86-64 icc 2021.3.0
x86-64 icc 2021.4.0
x86-64 icc 2021.5.0
x86-64 icx 2021.1.2
x86-64 icx 2021.2.0
x86-64 icx 2021.3.0
x86-64 icx 2021.4.0
x86-64 icx 2022.0.0
zig c++ 0.6.0
zig c++ 0.7.0
zig c++ 0.7.1
zig c++ 0.8.0
zig c++ 0.9.0
zig c++ trunk
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Source code
// Hypothetical Rust-like owner / borrow wrappers in C++ // This wraps types with data which is compiled away in release // It is not possible to static_assert, so this uses static ints to count errors. #include <utility> // Statics to track errors. Ideally these would be static_asserts // but they depen on Owner::has_been_moved which changes during compilation. static int owner_already_moved = 0; static int owner_use_after_move = 0; static int owner_already_borrowed = 0; // This method exists to ensure static errors are reported in compiler explorer int get_fault_count() { return owner_already_moved + owner_use_after_move + owner_already_borrowed; } // Storage for ownership of a type T. // Equivalent to mut usage in Rust // Disallows move by value, instead ownership must be explicitly moved. template <typename T> struct Owner { Owner(T v) : value(v) {} Owner(Owner<T>& ov) = delete; Owner(Owner<T>&& ov) { if (ov.has_been_moved) { owner_already_moved++; } value = std::move(ov.value); ov.has_been_moved = true; } T& operator*() { if (has_been_moved) { owner_use_after_move++; } return value; } T value; bool has_been_moved{false}; }; // Safely borrow a value of type T // Implicit constuction from Owner of same type to check borrow is safe template <typename T> struct Borrower { Borrower(Owner<T>& v) : value(v.value) { if (v.has_been_moved) { owner_already_borrowed++; } } const T& operator*() const { return value; } T value; }; // Example of function borrowing a value, can only read const ref static void use(Borrower<int> v) { (void)*v; } // Example of function taking ownership of value, can mutate via owner ref static void use_mut(Owner<int> v) { *v = 5; } int main() { // Rather than just 'int', Owner<int> tracks the lifetime of the value Owner<int> x{3}; // Borrowing value before mutating causes no problems use(x); // Mutating value passes ownership, has_been_moved set on original x use_mut(std::move(x)); // Uncomment for owner_already_borrowed = 1 //use(x); // Uncomment for owner_already_moved = 1 //use_mut(std::move(x)); // Uncomment for another owner_already_borrowed++ //Borrower<int> y = x; //Uncomment for owner_use_after_move = 1; //return *x; }
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