Clang does not support -march=native for all targets.
Arguably it should always work, but in reality it gives:
error: the clang compiler does not support '-march=native'
If we move CPU detection logic into Zig itelf, we will not need this,
instead we will always pass target features and CPU configuration explicitly.
For now, we simply avoid passing the flag when it is known to not be
supported.
This reverts commit ec7d7a5b14, reversing
changes made to 81c441f885.
It looks like this broke colors in Windows Command Prompt (#3147)
and this method of detecting native C ABI isn't working well (#3121).
Zig provides a libc for the GNU C ABI on Windows, and cannot (at least
yet) provide one for the MSVC C ABI. However when not linking libc,
zig has no problem targeting MSVC as the C ABI. And this should be the
default.
Related: #2911
* fixed --verbose-cc printing an extra "zig" before the rest of
the command line
* windows-gnu targets use libfoo.a, foo.o extensions to match mingw
conventions.
windows.h has files such as pshpack1.h which do #pragma packing,
triggering a clang warning. So for this target, this warning is
disabled.
this commit also improves the error message printed when no libc can be
used, printing the "zig triple" rather than the "llvm triple".
Fixes glibc_version being set to garbage. I've made this mistake
before so this is an attempt to prevent future bugs. Zig doesn't
have zero-initialization, so are we being a hypocrite by using this
C feature? No, because C doesn't have the feature that forces you to
initialize all fields. That would have prevented this bug every single
time.
* build-exe does include the startup code that supplies _start for the
wasm32-freestanding target. Previously this did not occur because
of logic excluding "freestanding".
* build-lib for wasm32-freestanding target gets linked by LLD. To avoid
infinite recursion, compiler_rt and zig libc are built as objects
rather than libraries.
- no "lib" prefix and ".wasm" extension instead of ".a". Rather than
build-lib foo.zig producing "libfoo.a", now it produces "foo.wasm".
* go back to using `.o` extension for webassembly objects
* zig libc only provides _start symbol for wasm when linking libc.
* rename std/special/builtin.zig to std/special/c.zig
not to be confused with @import("builtin") which is entirely
different, this is zig's multi-target libc implementation.
* WebAssembly: build-exe is for executables which have a main().
build-lib is for building libraries of functions to use from,
for example, a web browser environment.
- for now pass --export-all for libraries when there are any
C objects because we have no way to detect the list of exports
when compiling C code.
- stop passing --no-entry for executables. if you want --no-entry
then use build-lib.
* make the "musl" ABI the default ABI for wasm32-freestanding.
* zig provides libc for wasm32-freestanding-musl.
Andrew Kelley