Use architecture-specific version of math.h

It looks like math.h is the _only_ file that is architecture specific,
and apparently I missed it while adding ARM support.

Makefile

@@ -26,12 +26,16 @@ sysroot-%/usr/include: update.sh src/usr/include
 
 sysroot-macos-x86_64: sysroot-macos-x86_64/usr/include sysroot-macos-x86_64/usr/lib/libSystem.dylib
 sysroot-macos-x86_64/usr/lib/libSystem.dylib:
+ mkdir -p sysroot-macos-x86_64/usr/include
+ cp -rp src/usr/include/x86_64/* sysroot-macos-x86_64/usr/include
  mkdir -p $(dir $@)
  $(CLANG) $(DYLDFLAGS) --target=x86_64-apple-macos10.12 -o $(dir $@)/libSystem.B.dylib src/x86_64/libSystem.s
  ln -sf libSystem.B.dylib $@
 
 sysroot-macos-arm64: sysroot-macos-arm64/usr/include sysroot-macos-arm64/usr/lib/libSystem.dylib
 sysroot-macos-arm64/usr/lib/libSystem.dylib:
+ mkdir -p sysroot-macos-arm64/usr/include
+ cp -rp src/usr/include/arm64/* sysroot-macos-arm64/usr/include
  mkdir -p $(dir $@)
  $(CLANG) $(DYLDFLAGS) --target=arm64-apple-macos11 -o $(dir $@)/libSystem.B.dylib src/x86_64/libSystem.s
  ln -sf libSystem.B.dylib $@

generate-stubs.py

@@ -36,7 +36,8 @@ def generateStubs(sysroot, outfile, target):
 
  # Parse the src/libSystem.h file to get a list of functions declared in libSystem.
  index = clang.cindex.Index.create()
- args = args=['--sysroot='+sysroot, '-Werror', '--target='+target]
+ arch = target.split('-')[0]
+ args = args=['--sysroot='+sysroot, '-isystem', sysroot+'/usr/include/'+arch, '-Werror', '--target='+target]
  tu = index.parse('src/libSystem.h', args=args)
  if len(tu.diagnostics):
  print('failed to extract function stubs using %s:' % args)

src/arm64/libSystem.s

@@ -28,30 +28,18 @@ ___error:
 .global ___fpclassify
 ___fpclassify:
 
-.global ___fpclassifyd
-___fpclassifyd:
-
 .global ___fpclassifyf
 ___fpclassifyf:
 
-.global ___inf
-___inf:
-
-.global ___inff
-___inff:
-
-.global ___infl
-___infl:
+.global ___fpclassifyl
+___fpclassifyl:
 
 .global ___math_errhandling
 ___math_errhandling:
 
 .global ___mb_cur_max
 ___mb_cur_max:
 
-.global ___nan
-___nan:
-
 .global ___opendir2
 ___opendir2:
 
@@ -415,9 +403,6 @@ _dprintf:
 .global _drand48
 _drand48:
 
-.global _drem
-_drem:
-
 .global _dup
 _dup:
 
@@ -631,9 +616,6 @@ _filesec_set_property:
 .global _filesec_unset_property
 _filesec_unset_property:
 
-.global _finite
-_finite:
-
 .global _flock
 _flock:
 
@@ -796,9 +778,6 @@ _futimens:
 .global _fwrite
 _fwrite:
 
-.global _gamma
-_gamma:
-
 .global _gcvt
 _gcvt:
 
@@ -1183,9 +1162,6 @@ _madvise:
 .global _malloc
 _malloc:
 
-.global _matherr
-_matherr:
-
 .global _mblen
 _mblen:
 
@@ -1618,9 +1594,6 @@ _rintf:
 .global _rintl
 _rintl:
 
-.global _rinttol
-_rinttol:
-
 .global _rmdir
 _rmdir:
 
@@ -1633,9 +1606,6 @@ _roundf:
 .global _roundl
 _roundl:
 
-.global _roundtol
-_roundtol:
-
 .global _rpmatch
 _rpmatch:
 
@@ -1804,9 +1774,6 @@ _signal:
 .global _signgam
 _signgam:
 
-.global _significand
-_significand:
-
 .global _sin
 _sin: