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Tangent: Is there a reason why C and C++ compilers are dev-PC-OS dependent for ARM targets? For example, if using Rust to compile for a Cortex-M etc, the workfl

Tangent: Is there a reason why C and C++ compilers are dev-PC-OS dependent for ARM targets? For example, if using Rust to compile for a Cortex-M etc, the workflow is the same for Windows and linux: Install the `thumbv7` target using a CLI command, then `cargo build`. I'm trying to build an OSS C lib now for the same platform, and the Windows instructions involve WSL or Cgywin.

rfoo 5y ago
No. The most likely reason in your case is the build system of the library you want to build uses some mix of POSIX shell script and GNU Make, which is ... hard to get right on Windows. It's not C/C++ specific, through installing a cross C compiler on Windows might involve more work than rustup add target (or not, if someone did the work and packaged the toolchain as .exe installer).
melissalobos 5y ago
Rust only uses LLVM currently. WSL or Cygwin is because the compiler situation on Windows is a bit rough(VS doesn't support C fully), so most people use GCC there.
- xvilka 5y ago
  > compiler situation on Windows is a bit rough(VS doesn't support C fully) clang-cl[1] does. [1] https://clang.llvm.org/docs/MSVCCompatibility.html https://clang.llvm.org/docs/MSVCCompatibility.html
- pjmlp 5y ago
  VS supports C11 and C17, to the extent required by the standard, minus optional annexes. The only thing missing are some atomic library calls.
  - uecker 5y ago
    Yes, almost. But it misses optional features and common extensions.
    - pjmlp 5y ago
      Optional features and extensions are exactly that. Optional and not expected to be supported by every compiler out there, otherwise they would be part of ISO requirements.
mhh__ 5y ago
It's basically an artifact of how GCC works. LLVM is a library that happens to have Clang in front of it, whereas GCC still isn't really able to have multiple targets in the same binary. Could probably be done but for actually assembling toolchains you generally only need one anyway so it's not that annoying most of the time.
- nicoburns 5y ago
  > but for actually assembling toolchains you generally only need one Not if you intend to ship on multiple platforms. Having to run builds on the native platform or install a separate cross-compilation toolchain is incredibly annoying (and difficult to get right to the point that it's common to not even try). It would be a big usability win if C toolchains could get cross-compilation to Go or Zig levels of "just works".
  - mhh__ 5y ago
    Sure but sometimes you need to get your hands on system libraries, C headers, linkers etc.

rfoo 5y ago

No. The most likely reason in your case is the build system of the library you want to build uses some mix of POSIX shell script and GNU Make, which is ... hard to get right on Windows. It's not C/C++ specific, through installing a cross C compiler on Windows might involve more work than rustup add target (or not, if someone did the work and packaged the toolchain as .exe installer).

melissalobos 5y ago

Rust only uses LLVM currently. WSL or Cygwin is because the compiler situation on Windows is a bit rough(VS doesn't support C fully), so most people use GCC there.

xvilka 5y ago
> compiler situation on Windows is a bit rough(VS doesn't support C fully) clang-cl[1] does. [1] https://clang.llvm.org/docs/MSVCCompatibility.html https://clang.llvm.org/docs/MSVCCompatibility.html
pjmlp 5y ago
VS supports C11 and C17, to the extent required by the standard, minus optional annexes. The only thing missing are some atomic library calls.
- uecker 5y ago
  Yes, almost. But it misses optional features and common extensions.
  - pjmlp 5y ago
    Optional features and extensions are exactly that. Optional and not expected to be supported by every compiler out there, otherwise they would be part of ISO requirements.

mhh__ 5y ago

It's basically an artifact of how GCC works. LLVM is a library that happens to have Clang in front of it, whereas GCC still isn't really able to have multiple targets in the same binary. Could probably be done but for actually assembling toolchains you generally only need one anyway so it's not that annoying most of the time.

nicoburns 5y ago
> but for actually assembling toolchains you generally only need one Not if you intend to ship on multiple platforms. Having to run builds on the native platform or install a separate cross-compilation toolchain is incredibly annoying (and difficult to get right to the point that it's common to not even try). It would be a big usability win if C toolchains could get cross-compilation to Go or Zig levels of "just works".
- mhh__ 5y ago
  Sure but sometimes you need to get your hands on system libraries, C headers, linkers etc.