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What the hell is a target triple?

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Re: What the hell is a target triple?

#121

Post by o11c »

jcranmer wrote: post #101
IshKebab wrote: post #70

Earlier quoted context omitted.

Nah I dunno where you're getting your information from but LLVM only supports 5 components. See the code starting at line 1144 here: https://llvm.org/doxygen/Triple_8cpp_source.html The components are arch-vendor-os-environment-objectformat. It's absolutely full of special cases and hacks. Really at this point I think the only sane option is an explicit list of fixed strings. I think Rust does that.

You're not really contradicting o11c here; what LLVM calls "environment" is a mixture of what they called libc/abi/fabi. There's also what LLVM calls "subarch" to distinguish between different architectures that may be relevant (e.g., i386 is not the same as i686, although LLVM doesn't record this difference since it's generally less interested in targeting old hardware), and there's also OS version numbers that may…

Hm, looking to see if the vendor field is actually meaningful ... I see some stuff for m68k and mips and sysv targets ... some of it working around pre-standard vendor C implementations

Ah, I found a modern one:

  i[3456789]86-w64-mingw* does not use winsup
  i[3456789]86-*-mingw* with other vendors does use winsup
There are probably more; this is embedded in all sorts of random configure scripts and it is very not-greppable.

Re: What the hell is a target triple?

#122

Post by naruhodo »

dharmab wrote: post #22
throw0101d wrote: post #15

Noticed endians listed in the table. It seems like little-endian has basically taken over the world in 2025: * https://en.wikipedia.org/wiki/Endianness#Hardware Is there anything that is used a lot that is not little? IBM's stuff? Network byte order is BE: * https://en.wikipedia.org/wiki/Endianness#Networking

LEON, used by the European Space Agency, is big endian.

Should have been called BEON.

Re: What the hell is a target triple?

#123

Post by fc417fc802 »

o11c wrote: post #107
matheusmoreira wrote: post #98

Earlier quoted context omitted.

It works fine on current Linux systems. We can have freestanding executables that talk to Linux directly and link against zero system libraries. It's just that those executables are going to have to resolve names all by themselves. Chances are they aren't going to do it exactly like glibc does. That may or may not be a problem.

Historically, when DNS breaks in a not-glibc environment, it's very often found to in fact be a violation of some standard by the not-glibc, rather than a program that fails to document a glibc dependency.

Just connect to the service running on localhost ...

I'm curious. Why isn't getaddrinfo implemented in a similar manner to the loaders that graphics APIs use? Shouldn't that functionality be the responsibility of whatever resolver has been installed?

Re: What the hell is a target triple?

#124

Post by IshKebab »

o11c wrote: post #73
IshKebab wrote: post #70

Earlier quoted context omitted.

Nah I dunno where you're getting your information from but LLVM only supports 5 components. See the code starting at line 1144 here: https://llvm.org/doxygen/Triple_8cpp_source.html The components are arch-vendor-os-environment-objectformat. It's absolutely full of special cases and hacks. Really at this point I think the only sane option is an explicit list of fixed strings. I think Rust does that.

LLVM didn't invent the scheme; why should we pay attention to their copy and not look at the original? The GNU Config project is the original.

The article goes into this a bit. But basically because LLVM is extremely popular and used as a backend by lots of other languages, e.g. Rust.

Frankly being the originators of this deranged scheme is a good reason not to listen to GNU!

Re: What the hell is a target triple?

#125

Post by fc417fc802 »

AKSF_Ackermann wrote: post #17
vient wrote: post #12

> Kalimba, VE > No idea what this is, and Google won’t help me. Seems that Kalimba is a DSP, originally by CSR and now by Qualcomm. CSR8640 is using it, for example https://www.qualcomm.com/products/internet-of-things/consume... VE is harder to find with such short name.

NEC Vector Engine. Basically not a thing outside supercomputers.

$800 for the 20B-P model on ebay. More memory bandwidth than a 4090. I wonder if llama.cpp could be made to run on it?

I see rumors they charge for the compiler though.

Re: What the hell is a target triple?

#126

Post by eqvinox »

matheusmoreira wrote: post #91
eqvinox wrote: post #44

Earlier quoted context omitted.

Given TFA's bias against GCC, I'm not so sure. e.g. looking at the linker script article… it's also missing the __start_XYZ and __stop_XYZ symbols automatically created by the linker.

It also focuses exclusively on sections. I wish it had at least mentioned segments, also known as program headers. Linux kernel's ELF loader does not care about sections, it only cares about segments. Sections and segments are more or less the same concept: metadata that tells the loader how to map each part of the file into the correct memory regions with the correct memory protection attributes. Biggest difference…

Absolutely agree. Had my own fun dealings with ELF, and to be clear, on plain mainline shipping products (amd64 Linux), not toys/exercise/funky embedded. (Wouldn't have known about section start/stop symbols otherwise)

Re: What the hell is a target triple?

#127

Post by f_devd »

forrestthewoods wrote: post #21
throw0101d wrote: post #15

Noticed endians listed in the table. It seems like little-endian has basically taken over the world in 2025: * https://en.wikipedia.org/wiki/Endianness#Hardware Is there anything that is used a lot that is not little? IBM's stuff? Network byte order is BE: * https://en.wikipedia.org/wiki/Endianness#Networking

BE isn’t technically dead buts it’s practically dead for almost all projects. You can static_assert byte order and then never think about BE ever again. All of my custom network serialization formats use LE because there’s literally no reason to use BE for network byte order. It’s pure legacy cruft.

...Until you find yourself having to workaround legacy code to support some weird target that does still use BE. Speaking from experience (tbf usually lower level than anything actually networked, more like RS485 and friends).

Re: What the hell is a target triple?

#128

Post by o11c »

fc417fc802 wrote: post #123
o11c wrote: post #107

Earlier quoted context omitted.

Historically, when DNS breaks in a not-glibc environment, it's very often found to in fact be a violation of some standard by the not-glibc, rather than a program that fails to document a glibc dependency.

Just connect to the service running on localhost ... I'm curious. Why isn't getaddrinfo implemented in a similar manner to the loaders that graphics APIs use? Shouldn't that functionality be the responsibility of whatever resolver has been installed?

That is how `getaddrinfo` works under GLIBC; it's called NSS. The problem (well, one of them) is the non-GLIBC implementations that say "we don't need no stinkin' loader!"

Re: What the hell is a target triple?

#129

Post by cestith »

> “i386” (the first Intel microarchitecture that implemented protected mode)12

This is technically incorrect. The 286 had protected mode. It was a 16-bit protected mode, being a 16-bit processor. It was also incompatible with the later protected mode of the 386 through today’s processors. It did, however, exist.

Re: What the hell is a target triple?

#130

Post by achierius »

lifthrasiir wrote: post #96
peterldowns wrote: post #24

Some other sources of target triples (some mentioned in the article, some not): rustc: `rustc --print target-list` golang: `go tool dist list` zig: `zig targets` As the article point out, the complete lack of standardization and consistency in what constitutes a "triple" (sometimes actually a quad!) is kind of hellishly hilarious.

> what constitutes a "triple" (sometimes actually a quad!) It is actually a quintiple at most because the first part, architecture, may contain a version for e.g. ARM. And yet it doesn't fully describe the actual target because it may require an additional OS version for e.g. macOS. Doubly silly.

Why would macOS in particular require an OS version where other platforms would not -- just backwards compatibility?
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