Instead of always supplying flags, apply the flags as defaults. Use
clang's native flags instead of lifting the linker flags from binutils
with `-Wl,`.
If a project is using clang to drive linking, make clang do the right
thing with MACOSX_DEPLOYMENT_TARGET. This can be overridden by command
line arguments. This will cause modern clang to pass
`-platform_version 10.12 0.0.0`, since it doesn't know about the SDK
settings. Older versions of clang will pass down `-macos_version_min`
flags with no sdk version.
At the linker layer, apply a default value for anything left
ambiguous. If nothing is specified, pass a full
`-platform_version`. If only `-macos_version_min` is specified, then
lock down the sdk_version explicitly with `-sdk_version`. If a min
version and sdk version is passed, do nothing.
The new skip for the dynamic linker introduced in
ccfd26ef14 ("bintools-wrapper: skip dynamic linker for static
binaries") includes a change in behaviour, previously the $link32
variable was checked using an arithmetic expression via (( )). This
returns zero if the output of the arithmetic expression is nonzero, i.e.
link32=1 would return zero and the if condition would be executed.
The code refactored this to use "$link32" = "0" which is incorrect in
this case, since we want this if conditional to run if $link32 is 1.
Small shell excerpt for clarity:
$ export link32=1
$ export cookie=1
$ if [[ "$cookie" = "1" ]] && (( "$link32" )); then echo "do some stuff"; fi;
do some stuff
$ if [[ "$cookie" = "1" && "$link32" = "0" ]]; then echo "do some stuff"; fi;
$
Change it to check for $link32 = "1", as the previous code did.
Currently we set dynamic-linker unconditionally. This breaks
however some static binaries i.e. rust binaries linked against musl.
There is no reason we should set an elf interpreter for static binaries
hence this is skipped if `-static` or `-static-pie` is either passed to
our cc or ld wrapper.
I hate the thing too even though I made it, and rather just get rid of
it. But we can't do that yet. In the meantime, this brings us more
inline with autoconf and will make it slightly easier for me to write a
pkg-config wrapper, which we need.
Factor a bintools (i.e. binutils / cctools) wrapper out of cc-wrapper. While
only LD is wrapped, the setup hook defines environment variables on behalf of
other utilites.
