Makefile

   1 # These variables are specifically meant to be overridable via the make
   2 # command-line.
   3 WASM_CC ?= clang
   4 WASM_NM ?= $(patsubst %clang,%llvm-nm,$(WASM_CC))
   5 WASM_AR ?= $(patsubst %clang,%llvm-ar,$(WASM_CC))
   6 WASM_CFLAGS ?= -O2 -DNDEBUG
   7 # The directory where we build the sysroot.
   8 SYSROOT ?= $(CURDIR)/sysroot
   9 # A directory to install to for "make install".
  10 INSTALL_DIR ?= /usr/local
  11 # single or posix
  12 THREAD_MODEL ?= single
  13 # yes or no
  14 BUILD_DLMALLOC ?= yes
  15 BUILD_LIBC_TOP_HALF ?= yes
  16 # The directory where we're store intermediate artifacts.
  17 OBJDIR ?= $(CURDIR)/build
  18
  19 # Check dependencies.
  20 ifneq ($(BUILD_DLMALLOC),yes)
  21 $(error build currently depends on BUILD_DLMALLOC=yes)
  22 endif
  23
  24 # Variables from this point on are not meant to be overridable via the
  25 # make command-line.
  26
  27 # Set the target variables. Multiarch triples notably omit the vendor field,
  28 # which happens to be what we do for the main target triple too.
  29 TARGET_TRIPLE = wasm32-wasi
  30 MULTIARCH_TRIPLE = wasm32-wasi
  31
  32 # These variables describe the locations of various files and directories in
  33 # the source tree.
  34 DLMALLOC_DIR = $(CURDIR)/dlmalloc
  35 DLMALLOC_SRC_DIR = $(DLMALLOC_DIR)/src
  36 DLMALLOC_SOURCES = $(DLMALLOC_SRC_DIR)/dlmalloc.c
  37 DLMALLOC_INC = $(DLMALLOC_DIR)/include
  38 LIBC_BOTTOM_HALF_DIR = $(CURDIR)/libc-bottom-half
  39 LIBC_BOTTOM_HALF_CLOUDLIBC_SRC = $(LIBC_BOTTOM_HALF_DIR)/cloudlibc/src
  40 LIBC_BOTTOM_HALF_CLOUDLIBC_SRC_INC = $(LIBC_BOTTOM_HALF_CLOUDLIBC_SRC)/include
  41 LIBC_BOTTOM_HALF_HEADERS_PUBLIC = $(LIBC_BOTTOM_HALF_DIR)/headers/public
  42 LIBC_BOTTOM_HALF_HEADERS_PRIVATE = $(LIBC_BOTTOM_HALF_DIR)/headers/private
  43 LIBC_BOTTOM_HALF_SOURCES = $(LIBC_BOTTOM_HALF_DIR)/sources
  44 LIBC_BOTTOM_HALF_ALL_SOURCES = \
  45     $(shell find $(LIBC_BOTTOM_HALF_CLOUDLIBC_SRC) -name \*.c) \
  46     $(shell find $(LIBC_BOTTOM_HALF_SOURCES) -name \*.c)
  47
  48 # FIXME(https://reviews.llvm.org/D85567) - due to a bug in LLD the weak
  49 # references to a function defined in `chdir.c` only work if `chdir.c` is at the
  50 # end of the archive, but once that LLD review lands and propagates into LLVM
  51 # then we don't have to do this.
  52 LIBC_BOTTOM_HALF_ALL_SOURCES := $(filter-out $(LIBC_BOTTOM_HALF_SOURCES)/chdir.c,$(LIBC_BOTTOM_HALF_ALL_SOURCES))
  53 LIBC_BOTTOM_HALF_ALL_SOURCES := $(LIBC_BOTTOM_HALF_ALL_SOURCES) $(LIBC_BOTTOM_HALF_SOURCES)/chdir.c
  54
  55 LIBWASI_EMULATED_MMAN_SOURCES = \
  56     $(shell find $(LIBC_BOTTOM_HALF_DIR)/mman -name \*.c)
  57 LIBWASI_EMULATED_SIGNAL_SOURCES = \
  58     $(shell find $(LIBC_BOTTOM_HALF_DIR)/signal -name \*.c)
  59 LIBWASI_EMULATED_SIGNAL_MUSL_SOURCES = \
  60     $(LIBC_TOP_HALF_MUSL_SRC_DIR)/signal/psignal.c \
  61     $(LIBC_TOP_HALF_MUSL_SRC_DIR)/string/strsignal.c
  62 LIBC_BOTTOM_HALF_CRT_SOURCES = $(wildcard $(LIBC_BOTTOM_HALF_DIR)/crt/*.c)
  63 LIBC_TOP_HALF_DIR = $(CURDIR)/libc-top-half
  64 LIBC_TOP_HALF_MUSL_DIR = $(LIBC_TOP_HALF_DIR)/musl
  65 LIBC_TOP_HALF_MUSL_SRC_DIR = $(LIBC_TOP_HALF_MUSL_DIR)/src
  66 LIBC_TOP_HALF_MUSL_INC = $(LIBC_TOP_HALF_MUSL_DIR)/include
  67 LIBC_TOP_HALF_MUSL_SOURCES = \
  68     $(addprefix $(LIBC_TOP_HALF_MUSL_SRC_DIR)/, \
  69         misc/a64l.c \
  70         misc/basename.c \
  71         misc/dirname.c \
  72         misc/ffs.c \
  73         misc/ffsl.c \
  74         misc/ffsll.c \
  75         misc/fmtmsg.c \
  76         misc/getdomainname.c \
  77         misc/gethostid.c \
  78         misc/getopt.c \
  79         misc/getopt_long.c \
  80         misc/getsubopt.c \
  81         misc/uname.c \
  82         misc/nftw.c \
  83         errno/strerror.c \
  84         network/htonl.c \
  85         network/htons.c \
  86         network/ntohl.c \
  87         network/ntohs.c \
  88         network/inet_ntop.c \
  89         network/inet_pton.c \
  90         network/inet_aton.c \
  91         network/in6addr_any.c \
  92         network/in6addr_loopback.c \
  93         fenv/fenv.c \
  94         fenv/fesetround.c \
  95         fenv/feupdateenv.c \
  96         fenv/fesetexceptflag.c \
  97         fenv/fegetexceptflag.c \
  98         fenv/feholdexcept.c \
  99         exit/exit.c \
 100         exit/atexit.c \
 101         exit/assert.c \
 102         exit/quick_exit.c \
 103         exit/at_quick_exit.c \
 104         time/strftime.c \
 105         time/asctime.c \
 106         time/asctime_r.c \
 107         time/ctime.c \
 108         time/ctime_r.c \
 109         time/wcsftime.c \
 110         time/strptime.c \
 111         time/difftime.c \
 112         time/timegm.c \
 113         time/ftime.c \
 114         time/gmtime.c \
 115         time/gmtime_r.c \
 116         time/timespec_get.c \
 117         time/getdate.c \
 118         time/localtime.c \
 119         time/localtime_r.c \
 120         time/mktime.c \
 121         time/__tm_to_secs.c \
 122         time/__month_to_secs.c \
 123         time/__secs_to_tm.c \
 124         time/__year_to_secs.c \
 125         time/__tz.c \
 126         fcntl/creat.c \
 127         dirent/alphasort.c \
 128         dirent/versionsort.c \
 129         env/clearenv.c \
 130         env/getenv.c \
 131         env/putenv.c \
 132         env/setenv.c \
 133         env/unsetenv.c \
 134         unistd/posix_close.c \
 135     ) \
 136     $(filter-out %/procfdname.c %/syscall.c %/syscall_ret.c %/vdso.c %/version.c, \
 137                  $(wildcard $(LIBC_TOP_HALF_MUSL_SRC_DIR)/internal/*.c)) \
 138     $(filter-out %/flockfile.c %/funlockfile.c %/__lockfile.c %/ftrylockfile.c \
 139                  %/rename.c \
 140                  %/tmpnam.c %/tmpfile.c %/tempnam.c \
 141                  %/popen.c %/pclose.c \
 142                  %/remove.c \
 143                  %/gets.c, \
 144                  $(wildcard $(LIBC_TOP_HALF_MUSL_SRC_DIR)/stdio/*.c)) \
 145     $(filter-out %/strsignal.c, \
 146                  $(wildcard $(LIBC_TOP_HALF_MUSL_SRC_DIR)/string/*.c)) \
 147     $(filter-out %/dcngettext.c %/textdomain.c %/bind_textdomain_codeset.c, \
 148                  $(wildcard $(LIBC_TOP_HALF_MUSL_SRC_DIR)/locale/*.c)) \
 149     $(wildcard $(LIBC_TOP_HALF_MUSL_SRC_DIR)/stdlib/*.c) \
 150     $(wildcard $(LIBC_TOP_HALF_MUSL_SRC_DIR)/search/*.c) \
 151     $(wildcard $(LIBC_TOP_HALF_MUSL_SRC_DIR)/multibyte/*.c) \
 152     $(wildcard $(LIBC_TOP_HALF_MUSL_SRC_DIR)/regex/*.c) \
 153     $(wildcard $(LIBC_TOP_HALF_MUSL_SRC_DIR)/prng/*.c) \
 154     $(wildcard $(LIBC_TOP_HALF_MUSL_SRC_DIR)/conf/*.c) \
 155     $(wildcard $(LIBC_TOP_HALF_MUSL_SRC_DIR)/ctype/*.c) \
 156     $(filter-out %/__signbit.c %/__signbitf.c %/__signbitl.c \
 157                  %/__fpclassify.c %/__fpclassifyf.c %/__fpclassifyl.c \
 158                  %/ceilf.c %/ceil.c \
 159                  %/floorf.c %/floor.c \
 160                  %/truncf.c %/trunc.c \
 161                  %/rintf.c %/rint.c \
 162                  %/nearbyintf.c %/nearbyint.c \
 163                  %/sqrtf.c %/sqrt.c \
 164                  %/fabsf.c %/fabs.c \
 165                  %/copysignf.c %/copysign.c \
 166                  %/fminf.c %/fmaxf.c \
 167                  %/fmin.c %/fmax.c, \
 168                  $(wildcard $(LIBC_TOP_HALF_MUSL_SRC_DIR)/math/*.c)) \
 169     $(filter-out %/crealf.c %/creal.c %creall.c \
 170                  %/cimagf.c %/cimag.c %cimagl.c, \
 171                  $(wildcard $(LIBC_TOP_HALF_MUSL_SRC_DIR)/complex/*.c)) \
 172     $(wildcard $(LIBC_TOP_HALF_MUSL_SRC_DIR)/crypt/*.c)
 173 MUSL_PRINTSCAN_SOURCES = \
 174     $(LIBC_TOP_HALF_MUSL_SRC_DIR)/internal/floatscan.c \
 175     $(LIBC_TOP_HALF_MUSL_SRC_DIR)/stdio/vfprintf.c \
 176     $(LIBC_TOP_HALF_MUSL_SRC_DIR)/stdio/vfwprintf.c \
 177     $(LIBC_TOP_HALF_MUSL_SRC_DIR)/stdio/vfscanf.c \
 178     $(LIBC_TOP_HALF_MUSL_SRC_DIR)/stdlib/strtod.c \
 179     $(LIBC_TOP_HALF_MUSL_SRC_DIR)/stdlib/wcstod.c
 180 LIBC_TOP_HALF_HEADERS_PRIVATE = $(LIBC_TOP_HALF_DIR)/headers/private
 181 LIBC_TOP_HALF_SOURCES = $(LIBC_TOP_HALF_DIR)/sources
 182 LIBC_TOP_HALF_ALL_SOURCES = \
 183     $(LIBC_TOP_HALF_MUSL_SOURCES) \
 184     $(shell find $(LIBC_TOP_HALF_SOURCES) -name \*.c)
 185
 186 # Set the target.
 187 CFLAGS = $(WASM_CFLAGS) --target=$(TARGET_TRIPLE)
 188 # WebAssembly floating-point match doesn't trap.
 189 # TODO: Add -fno-signaling-nans when the compiler supports it.
 190 CFLAGS += -fno-trapping-math
 191 # Add all warnings, but disable a few which occur in third-party code.
 192 CFLAGS += -Wall -Wextra -Werror \
 193   -Wno-null-pointer-arithmetic \
 194   -Wno-unused-parameter \
 195   -Wno-sign-compare \
 196   -Wno-unused-variable \
 197   -Wno-unused-function \
 198   -Wno-ignored-attributes \
 199   -Wno-missing-braces \
 200   -Wno-ignored-pragmas
 201
 202 # Configure support for threads.
 203 ifeq ($(THREAD_MODEL), single)
 204 CFLAGS += -mthread-model single
 205 endif
 206 ifeq ($(THREAD_MODEL), posix)
 207 CFLAGS += -mthread-model posix -pthread
 208 endif
 209
 210 # Set the sysroot.
 211 CFLAGS += --sysroot="$(SYSROOT)"
 212
 213 # These variables describe the locations of various files and directories in
 214 # the build tree.
 215 objs = $(patsubst $(CURDIR)/%.c,$(OBJDIR)/%.o,$(1))
 216 DLMALLOC_OBJS = $(call objs,$(DLMALLOC_SOURCES))
 217 LIBC_BOTTOM_HALF_ALL_OBJS = $(call objs,$(LIBC_BOTTOM_HALF_ALL_SOURCES))
 218 LIBC_TOP_HALF_ALL_OBJS = $(call objs,$(LIBC_TOP_HALF_ALL_SOURCES))
 219 ifeq ($(BUILD_DLMALLOC),yes)
 220 LIBC_OBJS += $(DLMALLOC_OBJS)
 221 endif
 222 # Add libc-bottom-half's objects.
 223 LIBC_OBJS += $(LIBC_BOTTOM_HALF_ALL_OBJS)
 224 ifeq ($(BUILD_LIBC_TOP_HALF),yes)
 225 # libc-top-half is musl.
 226 LIBC_OBJS += $(LIBC_TOP_HALF_ALL_OBJS)
 227 endif
 228 MUSL_PRINTSCAN_OBJS = $(call objs,$(MUSL_PRINTSCAN_SOURCES))
 229 MUSL_PRINTSCAN_LONG_DOUBLE_OBJS = $(patsubst %.o,%.long-double.o,$(MUSL_PRINTSCAN_OBJS))
 230 MUSL_PRINTSCAN_NO_FLOATING_POINT_OBJS = $(patsubst %.o,%.no-floating-point.o,$(MUSL_PRINTSCAN_OBJS))
 231 LIBWASI_EMULATED_MMAN_OBJS = $(call objs,$(LIBWASI_EMULATED_MMAN_SOURCES))
 232 LIBWASI_EMULATED_SIGNAL_OBJS = $(call objs,$(LIBWASI_EMULATED_SIGNAL_SOURCES))
 233 LIBWASI_EMULATED_SIGNAL_MUSL_OBJS = $(call objs,$(LIBWASI_EMULATED_SIGNAL_MUSL_SOURCES))
 234
 235 # These variables describe the locations of various files and
 236 # directories in the generated sysroot tree.
 237 SYSROOT_LIB := $(SYSROOT)/lib/$(MULTIARCH_TRIPLE)
 238 SYSROOT_INC = $(SYSROOT)/include
 239 SYSROOT_SHARE = $(SYSROOT)/share/$(MULTIARCH_TRIPLE)
 240
 241 # Files from musl's include directory that we don't want to install in the
 242 # sysroot's include directory.
 243 MUSL_OMIT_HEADERS :=
 244
 245 # Remove files which aren't headers (we generate alltypes.h below).
 246 MUSL_OMIT_HEADERS += \
 247     "bits/syscall.h.in" \
 248     "bits/alltypes.h.in" \
 249     "alltypes.h.in"
 250
 251 # Use the compiler's version of these headers.
 252 MUSL_OMIT_HEADERS += \
 253     "stdarg.h" \
 254     "stddef.h"
 255
 256 # Use the WASI errno definitions.
 257 MUSL_OMIT_HEADERS += \
 258     "bits/errno.h"
 259
 260 # Remove headers that aren't supported yet or that aren't relevant for WASI.
 261 MUSL_OMIT_HEADERS += \
 262     "sys/procfs.h" \
 263     "sys/user.h" \
 264     "sys/kd.h" "sys/vt.h" "sys/soundcard.h" "sys/sem.h" \
 265     "sys/shm.h" "sys/msg.h" "sys/ipc.h" "sys/ptrace.h" \
 266     "sys/statfs.h" \
 267     "bits/kd.h" "bits/vt.h" "bits/soundcard.h" "bits/sem.h" \
 268     "bits/shm.h" "bits/msg.h" "bits/ipc.h" "bits/ptrace.h" \
 269     "bits/statfs.h" \
 270     "sys/vfs.h" \
 271     "sys/statvfs.h" \
 272     "syslog.h" "sys/syslog.h" \
 273     "wait.h" "sys/wait.h" \
 274     "ucontext.h" "sys/ucontext.h" \
 275     "paths.h" \
 276     "utmp.h" "utmpx.h" \
 277     "lastlog.h" \
 278     "sys/acct.h" \
 279     "sys/cachectl.h" \
 280     "sys/epoll.h" "sys/reboot.h" "sys/swap.h" \
 281     "sys/sendfile.h" "sys/inotify.h" \
 282     "sys/quota.h" \
 283     "sys/klog.h" \
 284     "sys/fsuid.h" \
 285     "sys/io.h" \
 286     "sys/prctl.h" \
 287     "sys/mtio.h" \
 288     "sys/mount.h" \
 289     "sys/fanotify.h" \
 290     "sys/personality.h" \
 291     "elf.h" "link.h" "bits/link.h" \
 292     "scsi/scsi.h" "scsi/scsi_ioctl.h" "scsi/sg.h" \
 293     "sys/auxv.h" \
 294     "pwd.h" "shadow.h" "grp.h" \
 295     "mntent.h" \
 296     "netdb.h" \
 297     "resolv.h" \
 298     "pty.h" \
 299     "dlfcn.h" \
 300     "setjmp.h" \
 301     "ulimit.h" \
 302     "sys/xattr.h" \
 303     "wordexp.h" \
 304     "spawn.h" \
 305     "sys/membarrier.h" \
 306     "sys/signalfd.h" \
 307     "termios.h" \
 308     "sys/termios.h" \
 309     "bits/termios.h" \
 310     "net/if.h" \
 311     "net/if_arp.h" \
 312     "net/ethernet.h" \
 313     "net/route.h" \
 314     "netinet/if_ether.h" \
 315     "netinet/ether.h" \
 316     "sys/timerfd.h" \
 317     "libintl.h" \
 318     "sys/sysmacros.h"
 319
 320 ifeq ($(THREAD_MODEL), single)
 321 # Remove headers not supported in single-threaded mode.
 322 MUSL_OMIT_HEADERS += "aio.h" "pthread.h"
 323 endif
 324
 325 default: finish
 326
 327 $(SYSROOT_LIB)/libc.a: $(LIBC_OBJS)
 328
 329 $(SYSROOT_LIB)/libc-printscan-long-double.a: $(MUSL_PRINTSCAN_LONG_DOUBLE_OBJS)
 330
 331 $(SYSROOT_LIB)/libc-printscan-no-floating-point.a: $(MUSL_PRINTSCAN_NO_FLOATING_POINT_OBJS)
 332
 333 $(SYSROOT_LIB)/libwasi-emulated-mman.a: $(LIBWASI_EMULATED_MMAN_OBJS)
 334
 335 $(SYSROOT_LIB)/libwasi-emulated-signal.a: $(LIBWASI_EMULATED_SIGNAL_OBJS) $(LIBWASI_EMULATED_SIGNAL_MUSL_OBJS)
 336
 337 %.a:
 338         @mkdir -p "$(@D)"
 339         # On Windows, the commandline for the ar invocation got too long, so it needs to be split up.
 340         $(WASM_AR) crs $@ $(wordlist 1, 199, $^)
 341         $(WASM_AR) crs $@ $(wordlist 200, 399, $^)
 342         $(WASM_AR) crs $@ $(wordlist 400, 599, $^)
 343         $(WASM_AR) crs $@ $(wordlist 600, 799, $^)
 344         # This might eventually overflow again, but at least it'll do so in a loud way instead of
 345         # silently dropping the tail.
 346         $(WASM_AR) crs $@ $(wordlist 800, 100000, $^)
 347
 348 $(MUSL_PRINTSCAN_OBJS): CFLAGS += \
 349             -D__wasilibc_printscan_no_long_double \
 350             -D__wasilibc_printscan_full_support_option="\"add -lc-printscan-long-double to the link command\""
 351
 352 $(MUSL_PRINTSCAN_NO_FLOATING_POINT_OBJS): CFLAGS += \
 353             -D__wasilibc_printscan_no_floating_point \
 354             -D__wasilibc_printscan_floating_point_support_option="\"remove -lc-printscan-no-floating-point from the link command\""
 355
 356 $(LIBWASI_EMULATED_SIGNAL_MUSL_OBJS): CFLAGS += \
 357             -D_WASI_EMULATED_SIGNAL
 358
 359 $(OBJDIR)/%.long-double.o: $(CURDIR)/%.c include_dirs
 360         @mkdir -p "$(@D)"
 361         "$(WASM_CC)" $(CFLAGS) -MD -MP -o $@ -c $<
 362
 363 $(OBJDIR)/%.no-floating-point.o: $(CURDIR)/%.c include_dirs
 364         @mkdir -p "$(@D)"
 365         "$(WASM_CC)" $(CFLAGS) -MD -MP -o $@ -c $<
 366
 367 $(OBJDIR)/%.o: $(CURDIR)/%.c include_dirs
 368         @mkdir -p "$(@D)"
 369         "$(WASM_CC)" $(CFLAGS) -MD -MP -o $@ -c $<
 370
 371 -include $(shell find $(OBJDIR) -name \*.d)
 372
 373 $(DLMALLOC_OBJS): CFLAGS += \
 374     -I$(DLMALLOC_INC)
 375
 376 startup_files $(LIBC_BOTTOM_HALF_ALL_OBJS): CFLAGS += \
 377     -I$(LIBC_BOTTOM_HALF_HEADERS_PRIVATE) \
 378     -I$(LIBC_BOTTOM_HALF_CLOUDLIBC_SRC_INC) \
 379     -I$(LIBC_BOTTOM_HALF_CLOUDLIBC_SRC)
 380
 381 $(LIBC_TOP_HALF_ALL_OBJS) $(MUSL_PRINTSCAN_LONG_DOUBLE_OBJS) $(MUSL_PRINTSCAN_NO_FLOATING_POINT_OBJS) $(LIBWASI_EMULATED_SIGNAL_MUSL_OBJS): CFLAGS += \
 382     -I$(LIBC_TOP_HALF_MUSL_SRC_DIR)/include \
 383     -I$(LIBC_TOP_HALF_MUSL_SRC_DIR)/internal \
 384     -I$(LIBC_TOP_HALF_MUSL_DIR)/arch/wasm32 \
 385     -I$(LIBC_TOP_HALF_MUSL_DIR)/arch/generic \
 386     -I$(LIBC_TOP_HALF_HEADERS_PRIVATE) \
 387     -Wno-parentheses \
 388     -Wno-shift-op-parentheses \
 389     -Wno-bitwise-op-parentheses \
 390     -Wno-logical-op-parentheses \
 391     -Wno-string-plus-int \
 392     -Wno-dangling-else \
 393     -Wno-unknown-pragmas
 394
 395 include_dirs:
 396         $(RM) -r "$(SYSROOT)"
 397
 398         #
 399         # Install the include files.
 400         #
 401         mkdir -p "$(SYSROOT_INC)"
 402         cp -r "$(LIBC_BOTTOM_HALF_HEADERS_PUBLIC)"/* "$(SYSROOT_INC)"
 403
 404         # Generate musl's bits/alltypes.h header.
 405         mkdir -p "$(SYSROOT_INC)/bits"
 406         sed -f $(LIBC_TOP_HALF_MUSL_DIR)/tools/mkalltypes.sed \
 407             $(LIBC_TOP_HALF_MUSL_DIR)/arch/wasm32/bits/alltypes.h.in \
 408             $(LIBC_TOP_HALF_MUSL_DIR)/include/alltypes.h.in \
 409             > "$(SYSROOT_INC)/bits/alltypes.h"
 410
 411         # Copy in the bulk of musl's public header files.
 412         cp -r "$(LIBC_TOP_HALF_MUSL_INC)"/* "$(SYSROOT_INC)"
 413         # Copy in the musl's "bits" header files.
 414         cp -r "$(LIBC_TOP_HALF_MUSL_DIR)"/arch/generic/bits/* "$(SYSROOT_INC)/bits"
 415         cp -r "$(LIBC_TOP_HALF_MUSL_DIR)"/arch/wasm32/bits/* "$(SYSROOT_INC)/bits"
 416
 417         # Remove selected header files.
 418         $(RM) $(patsubst %,$(SYSROOT_INC)/%,$(MUSL_OMIT_HEADERS))
 419
 420 startup_files: include_dirs
 421         #
 422         # Build the startup files.
 423         #
 424         @mkdir -p "$(OBJDIR)"
 425         cd "$(OBJDIR)" && \
 426         "$(WASM_CC)" $(CFLAGS) -c $(LIBC_BOTTOM_HALF_CRT_SOURCES) -MD -MP && \
 427         mkdir -p "$(SYSROOT_LIB)" && \
 428         mv *.o "$(SYSROOT_LIB)"
 429
 430 libc: include_dirs \
 431     $(SYSROOT_LIB)/libc.a \
 432     $(SYSROOT_LIB)/libc-printscan-long-double.a \
 433     $(SYSROOT_LIB)/libc-printscan-no-floating-point.a \
 434     $(SYSROOT_LIB)/libwasi-emulated-mman.a \
 435     $(SYSROOT_LIB)/libwasi-emulated-signal.a
 436
 437 finish: startup_files libc
 438         #
 439         # Create empty placeholder libraries.
 440         #
 441         for name in m rt pthread crypt util xnet resolv dl; do \
 442             $(WASM_AR) crs "$(SYSROOT_LIB)/lib$${name}.a"; \
 443         done
 444
 445         #
 446         # Collect metadata on the sysroot and perform sanity checks.
 447         #
 448         mkdir -p "$(SYSROOT_SHARE)"
 449
 450         #
 451         # Collect symbol information.
 452         #
 453         @# TODO: Use llvm-nm --extern-only instead of grep. This is blocked on
 454         @# LLVM PR40497, which is fixed in 9.0, but not in 8.0.
 455         @# Ignore certain llvm builtin symbols such as those starting with __mul
 456         @# since these dependencies can vary between llvm versions.
 457         "$(WASM_NM)" --defined-only "$(SYSROOT_LIB)"/libc.a "$(SYSROOT_LIB)"/*.o \
 458             |grep ' [[:upper:]] ' |sed 's/.* [[:upper:]] //' |LC_ALL=C sort > "$(SYSROOT_SHARE)/defined-symbols.txt"
 459         for undef_sym in $$("$(WASM_NM)" --undefined-only "$(SYSROOT_LIB)"/libc.a "$(SYSROOT_LIB)"/libc-*.a "$(SYSROOT_LIB)"/*.o \
 460             |grep ' U ' |sed 's/.* U //' |LC_ALL=C sort |uniq); do \
 461             grep -q '\<'$$undef_sym'\>' "$(SYSROOT_SHARE)/defined-symbols.txt" || echo $$undef_sym; \
 462         done | grep -v "^__mul" > "$(SYSROOT_SHARE)/undefined-symbols.txt"
 463         grep '^_*imported_wasi_' "$(SYSROOT_SHARE)/undefined-symbols.txt" \
 464             > "$(SYSROOT_LIB)/libc.imports"
 465
 466         #
 467         # Generate a test file that includes all public header files.
 468         #
 469         cd "$(SYSROOT)" && \
 470           for header in $$(find include -type f -not -name mman.h -not -name signal.h |grep -v /bits/); do \
 471               echo '#include <'$$header'>' | sed 's/include\///' ; \
 472         done |LC_ALL=C sort >share/$(MULTIARCH_TRIPLE)/include-all.c ; \
 473         cd - >/dev/null
 474
 475         #
 476         # Test that it compiles.
 477         #
 478         "$(WASM_CC)" $(CFLAGS) -fsyntax-only "$(SYSROOT_SHARE)/include-all.c" -Wno-\#warnings
 479
 480         #
 481         # Collect all the predefined macros, except for compiler version macros
 482         # which we don't need to track here.
 483         #
 484         @#
 485         @# For the __*_ATOMIC_*_LOCK_FREE macros, squash individual compiler names
 486         @# to attempt, toward keeping these files compiler-independent.
 487         @#
 488         @# We have to add `-isystem $(SYSROOT_INC)` because otherwise clang puts
 489         @# its builtin include path first, which produces compiler-specific
 490         @# output.
 491         @#
 492         @# TODO: Undefine __FLOAT128__ for now since it's not in clang 8.0.
 493         @# TODO: Filter out __FLT16_* for now, as not all versions of clang have these.
 494         "$(WASM_CC)" $(CFLAGS) "$(SYSROOT_SHARE)/include-all.c" \
 495             -isystem $(SYSROOT_INC) \
 496             -std=gnu17 \
 497             -E -dM -Wno-\#warnings \
 498             -D_ALL_SOURCE \
 499             -U__llvm__ \
 500             -U__clang__ \
 501             -U__clang_major__ \
 502             -U__clang_minor__ \
 503             -U__clang_patchlevel__ \
 504             -U__clang_version__ \
 505             -U__GNUC__ \
 506             -U__GNUC_MINOR__ \
 507             -U__GNUC_PATCHLEVEL__ \
 508             -U__VERSION__ \
 509             -U__FLOAT128__ \
 510             | sed -e 's/__[[:upper:][:digit:]]*_ATOMIC_\([[:upper:][:digit:]_]*\)_LOCK_FREE/__compiler_ATOMIC_\1_LOCK_FREE/' \
 511             | grep -v '^#define __FLT16_' \
 512             > "$(SYSROOT_SHARE)/predefined-macros.txt"
 513
 514         # Check that the computed metadata matches the expected metadata.
 515         # This ignores whitespace because on Windows the output has CRLF line endings.
 516         diff -wur "$(CURDIR)/expected/$(MULTIARCH_TRIPLE)" "$(SYSROOT_SHARE)"
 517
 518         #
 519         # The build succeeded! The generated sysroot is in $(SYSROOT).
 520         #
 521
 522 install: finish
 523         mkdir -p "$(INSTALL_DIR)"
 524         cp -r "$(SYSROOT)/lib" "$(SYSROOT)/share" "$(SYSROOT)/include" "$(INSTALL_DIR)"
 525
 526 .PHONY: default startup_files libc finish install include_dirs