Possibly wrong constant values on any(target_os = "teeos", all(target_os = "linux", target_env = "uclibc", target_arch = "x86_64"))

[ramhugger]

Greetings,
I may have found a small set of constants whose values were included in libc as decimal literals while in fact they were written as octal literals in C. I believe this is the case because in C an integer literal that begins with a '0' is considered an octal literal, whereas in Rust the leading '0' is silently discarded.

I first noticed this while inspecting the value of O_NONBLOCK of another platform for a project of mine, and I noticed it had this declaration on Linux uClibc x86_64, which was inconsistent with all the other related values. This convinced me to investigate further, and I ran a RegExp against libc's codebase, which resulted in a small subset of constants (most are related to fcntl.h):

Before filing this issue, in order to be as sure and detailed as possible, I also went and gave a read to uClibc's Linux fcntl.h file, which uses in fact octal literals to declare the affected constants' values.

TL;DR

The constants listed above were likely copy-pasted from their respective headers and the subtle differences in integer literal rules from Rust and C lead to "wrong" values sneaking into the library...
unless I missed something and rustc is able to correctly interpret those literals as octals, which I unfortunately haven't been able to test on a Linux machine at the time of writing.

[tgross35]

Thanks for the catch! Could you put up a PR?

Also, do you have a link to the relevant teeos headers / docs?

libc location of the initial example (inline code or links is much preferred to screenshots)

libc/src/teeos/mod.rs

Line 180 in 1ffe0bd

pub const O_CREAT: u32 = 0100;