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6502 cc65 2.17
6502 cc65 2.18
6502 cc65 2.19
6502 cc65 trunk
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)
ARM gcc 11.2 (linux)
ARM gcc 11.2.1 (none)
ARM gcc 11.3 (linux)
ARM gcc 12.1 (linux)
ARM gcc 4.5.4 (linux)
ARM gcc 4.6.4 (linux)
ARM gcc 5.4 (linux)
ARM gcc 5.4.1 (none)
ARM gcc 6.3.0 (linux)
ARM gcc 6.4 (linux)
ARM gcc 7.2.1 (none)
ARM gcc 7.3 (linux)
ARM gcc 7.5 (linux)
ARM gcc 8.2 (WinCE)
ARM gcc 8.2 (linux)
ARM gcc 8.3.1 (none)
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 Morello gcc 10.1 Alpha 1
ARM64 gcc 10.2
ARM64 gcc 10.3
ARM64 gcc 11.1
ARM64 gcc 11.2
ARM64 gcc 11.3
ARM64 gcc 12.1
ARM64 gcc 5.4
ARM64 gcc 6.3
ARM64 gcc 6.4
ARM64 gcc 7.3
ARM64 gcc 7.5
ARM64 gcc 8.2
ARM64 gcc 8.5
ARM64 gcc 9.3
ARM64 gcc trunk
ARM64 msvc v19.14 (WINE)
AVR gcc 10.3.0
AVR gcc 11.1.0
AVR gcc 4.5.4
AVR gcc 4.6.4
AVR gcc 5.4.0
AVR gcc 9.2.0
AVR gcc 9.3.0
Arduino Mega (1.8.9)
Arduino Uno (1.8.9)
Chibicc 2020-12-07
FRC 2019
FRC 2020
K1C gcc 7.4
K1C gcc 7.5
KVX gcc 7.5 (ACB 4.1.0)
KVX gcc 7.5 (ACB 4.1.0-cd1)
KVX gcc 7.5 (ACB 4.2.0)
KVX gcc 7.5 (ACB 4.3.0)
KVX gcc 7.5 (ACB 4.4.0)
KVX gcc 9.4 (ACB 4.6.0)
MRISC32 gcc (trunk)
MSP430 gcc 4.5.3
MSP430 gcc 5.3.0
MSP430 gcc 6.2.1
RISC-V rv32gc clang (trunk)
RISC-V rv32gc clang 10.0.0
RISC-V rv32gc clang 10.0.1
RISC-V rv32gc clang 11.0.0
RISC-V rv32gc clang 11.0.1
RISC-V rv32gc clang 12.0.0
RISC-V rv32gc clang 12.0.1
RISC-V rv32gc clang 13.0.0
RISC-V rv32gc clang 13.0.1
RISC-V rv32gc clang 14.0.0
RISC-V rv32gc clang 9.0.0
RISC-V rv32gc clang 9.0.1
RISC-V rv32gc gcc 10.2.0
RISC-V rv32gc gcc 10.3.0
RISC-V rv32gc gcc 11.2.0
RISC-V rv32gc gcc 11.3.0
RISC-V rv32gc gcc 12.1.0
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
RISC-V rv64gc clang 11.0.1
RISC-V rv64gc clang 12.0.0
RISC-V rv64gc clang 12.0.1
RISC-V rv64gc clang 13.0.0
RISC-V rv64gc clang 13.0.1
RISC-V rv64gc clang 14.0.0
RISC-V rv64gc clang 9.0.0
RISC-V rv64gc clang 9.0.1
RISC-V rv64gc gcc 10.2.0
RISC-V rv64gc gcc 10.3.0
RISC-V rv64gc gcc 11.2.0
RISC-V rv64gc gcc 11.3.0
RISC-V rv64gc gcc 12.1.0
RISC-V rv64gc gcc 8.2.0
RISC-V rv64gc gcc 8.5.0
RISC-V rv64gc gcc 9.4.0
Raspbian Buster
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SDCC 4.0.0
SDCC 4.1.0
TCC (trunk)
TCC 0.9.27
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)
Xtensa ESP32 gcc 8.4.0 (2021r2)
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
cproc-master
mips (el) gcc 12.1.0
mips (el) gcc 5.4
mips gcc 11.2.0
mips gcc 12.1.0
mips gcc 5.4
mips gcc 9.3.0
mips64 (el) gcc 12.1.0
mips64 (el) gcc 5.4
mips64 gcc 11.2.0
mips64 gcc 12.1.0
mips64 gcc 5.4
nanoMIPS gcc 6.3.0
power gcc 11.2.0
power gcc 12.1.0
power gcc 4.8.5
power64 AT12.0 (gcc8)
power64 AT13.0 (gcc9)
power64 gcc 11.2.0
power64 gcc 12.1.0
power64le AT12.0 (gcc8)
power64le AT13.0 (gcc9)
power64le clang (trunk)
power64le gcc 11.2.0
power64le gcc 12.1.0
power64le gcc 6.3.0
powerpc64 clang (trunk)
ppci 0.5.5
s390x gcc 11.2.0
s390x gcc 12.1.0
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
x64 msvc v19.21
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 gcc 1.27
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 tendra (trunk)
x86-64 clang (assertions trunk)
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 (static analysis)
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 6.1
x86-64 gcc 6.2
x86-64 gcc 6.3
x86-64 gcc 7.1
x86-64 gcc 7.2
x86-64 gcc 7.3
x86-64 gcc 7.4
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 cc 0.6.0
zig cc 0.7.0
zig cc 0.7.1
zig cc 0.8.0
zig cc 0.9.0
zig cc trunk
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Source code
// public declaration // this is a shell type. // real definition lies within the unit. // `meters` is a POD type, and be copied. // `meters` can also be initialized with `memset()` #define METERS_SIZE 8 typedef union { char body[METERS_SIZE]; unsigned align4; // ensures `meters` is aligned on 4-bytes boundaries } meters; meters meters_init(int i); meters meters_add(meters a, meters b); // within unit #include <string.h> // memset #include <assert.h> // static_assert typedef enum { just, an, example } tag; typedef struct { int m; tag t; } meters_internal; // ensure shell type is large enough static_assert(sizeof(meters) >= sizeof(meters_internal), "meters shell type is too small"); // Don't alias pointers of different types. // shell and internal types are different ! meters meters_init_byref_incorrect(int i) { meters r; meters_internal* mptr = (meters_internal*)&r; // using a pointer in the hope to save one memory space mptr->m = i; mptr->t = example; return r; // notice the compiler believes that r is potentially uninitialized // because operations on mptr are not tracked as impacting r // since mptr and &r have different types. // In the end, it still generates correct output (see assembly on right pane), // but it's invitation for troubles, more complex cases might not work so well. } // Use memcpy to safely transport data // from shell to internal type, and vice versa. meters meters_init_memcpy_correct(int i) { meters_internal m; m.m = i; m.t = example; meters r; memcpy(&r, &m, sizeof(m)); // don't worry, the compiler will be clever enough to avoid this memcpy return r; }
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