Ada, Modula-2 (both available on GCC), D (available on its reference implementation, GCC and LLVM), Swift, Object Pascal (Free Pascal, Delphi, Oxygen), Oberon variants (Oberon, Oberon-2, Oberon-07, Active Oberon, Component Pascal), Zig, Nim, Odin,...
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Ada, Modula-2 (both available on GCC), D (available on its reference implementation, GCC and LLVM), Swift, Object Pascal (Free Pascal, Delphi, Oxygen), Oberon variants (Oberon, Oberon-2, Oberon-07, Active Oberon, Component Pascal), Zig, Nim, Odin,...
Zig definitely has undefined behavior
https://ziglang.org/documentation/0.13.0/#Undefined-Behavior
All systems programming languages have undefined behaviour, the golden question is how much.
Also it wasn't what the parent asked for, and I quote: "close to the hardware" language