configure

   1 #!/bin/sh
   2
   3 usage () {
   4 cat <<EOF
   5 Usage: $0 [OPTION]... [VAR=VALUE]... [TARGET]
   6
   7 To assign environment variables (e.g., CC, CFLAGS...), specify them as
   8 VAR=VALUE.  See below for descriptions of some of the useful variables.
   9
  10 Defaults for the options are specified in brackets.
  11
  12 Configuration:
  13   --srcdir=DIR            source directory [detected]
  14
  15 Installation directories:
  16   --prefix=PREFIX         main installation prefix [/usr/local/musl]
  17   --exec-prefix=EPREFIX   installation prefix for executable files [PREFIX]
  18
  19 Fine tuning of the installation directories:
  20   --bindir=DIR            user executables [EPREFIX/bin]
  21   --libdir=DIR            library files for the linker [PREFIX/lib]
  22   --includedir=DIR        include files for the C compiler [PREFIX/include]
  23   --syslibdir=DIR         location for the dynamic linker [/lib]
  24
  25 System types:
  26   --target=TARGET         configure to run on target TARGET [detected]
  27   --host=HOST             same as --target
  28   --build=BUILD           build system type; used only to infer cross-compiling
  29
  30 Optional features:
  31   --enable-optimize=...   optimize listed components for speed over size [auto]
  32   --enable-debug          build with debugging information [disabled]
  33   --enable-warnings       build with recommended warnings flags [disabled]
  34   --enable-wrapper=...    build given musl toolchain wrapper [auto]
  35   --disable-shared        inhibit building shared library [enabled]
  36   --disable-static        inhibit building static library [enabled]
  37
  38 Some influential environment variables:
  39   CC                      C compiler command [detected]
  40   CFLAGS                  C compiler flags [-Os -pipe ...]
  41   CROSS_COMPILE           prefix for cross compiler and tools [none]
  42   LIBCC                   compiler runtime library [detected]
  43
  44 Use these variables to override the choices made by configure.
  45
  46 EOF
  47 exit 0
  48 }
  49
  50 # Helper functions
  51
  52 quote () {
  53 tr '\n' ' ' <<EOF | grep '^[-[:alnum:]_=,./:]* $' >/dev/null 2>&1 && { echo "$1" ; return 0 ; }
  54 $1
  55 EOF
  56 printf %s\\n "$1" | sed -e "s/'/'\\\\''/g" -e "1s/^/'/" -e "\$s/\$/'/" -e "s#^'\([-[:alnum:]_,./:]*\)=\(.*\)\$#\1='\2#"
  57 }
  58 echo () { printf "%s\n" "$*" ; }
  59 fail () { echo "$*" ; exit 1 ; }
  60 fnmatch () { eval "case \"\$2\" in $1) return 0 ;; *) return 1 ;; esac" ; }
  61 cmdexists () { type "$1" >/dev/null 2>&1 ; }
  62 trycc () { test -z "$CC" && cmdexists "$1" && CC=$1 ; }
  63
  64 stripdir () {
  65 while eval "fnmatch '*/' \"\${$1}\"" ; do eval "$1=\${$1%/}" ; done
  66 }
  67
  68 trycppif () {
  69 printf "checking preprocessor condition %s... " "$1"
  70 echo "typedef int x;" > "$tmpc"
  71 echo "#if $1" >> "$tmpc"
  72 echo "#error yes" >> "$tmpc"
  73 echo "#endif" >> "$tmpc"
  74 if $CC $2 -c -o /dev/null "$tmpc" >/dev/null 2>&1 ; then
  75 printf "false\n"
  76 return 1
  77 else
  78 printf "true\n"
  79 return 0
  80 fi
  81 }
  82
  83 tryflag () {
  84 printf "checking whether compiler accepts %s... " "$2"
  85 echo "typedef int x;" > "$tmpc"
  86 if $CC $CFLAGS_TRY $2 -c -o /dev/null "$tmpc" >/dev/null 2>&1 ; then
  87 printf "yes\n"
  88 eval "$1=\"\${$1} \$2\""
  89 eval "$1=\${$1# }"
  90 return 0
  91 else
  92 printf "no\n"
  93 return 1
  94 fi
  95 }
  96
  97 tryldflag () {
  98 printf "checking whether linker accepts %s... " "$2"
  99 echo "typedef int x;" > "$tmpc"
 100 if $CC $LDFLAGS_TRY -nostdlib -shared "$2" -o /dev/null "$tmpc" >/dev/null 2>&1 ; then
 101 printf "yes\n"
 102 eval "$1=\"\${$1} \$2\""
 103 eval "$1=\${$1# }"
 104 return 0
 105 else
 106 printf "no\n"
 107 return 1
 108 fi
 109 }
 110
 111
 112
 113 # Beginning of actual script
 114
 115 CFLAGS_C99FSE=
 116 CFLAGS_AUTO=
 117 CFLAGS_MEMOPS=
 118 CFLAGS_NOSSP=
 119 CFLAGS_TRY=
 120 LDFLAGS_AUTO=
 121 LDFLAGS_TRY=
 122 OPTIMIZE_GLOBS=
 123 srcdir=
 124 prefix=/usr/local/musl
 125 exec_prefix='$(prefix)'
 126 bindir='$(exec_prefix)/bin'
 127 libdir='$(prefix)/lib'
 128 includedir='$(prefix)/include'
 129 syslibdir='/lib'
 130 tools=
 131 tool_libs=
 132 build=
 133 target=
 134 optimize=auto
 135 debug=no
 136 warnings=no
 137 shared=auto
 138 static=yes
 139 wrapper=auto
 140 gcc_wrapper=no
 141 clang_wrapper=no
 142
 143 for arg ; do
 144 case "$arg" in
 145 --help|-h) usage ;;
 146 --srcdir=*) srcdir=${arg#*=} ;;
 147 --prefix=*) prefix=${arg#*=} ;;
 148 --exec-prefix=*) exec_prefix=${arg#*=} ;;
 149 --bindir=*) bindir=${arg#*=} ;;
 150 --libdir=*) libdir=${arg#*=} ;;
 151 --includedir=*) includedir=${arg#*=} ;;
 152 --syslibdir=*) syslibdir=${arg#*=} ;;
 153 --enable-shared|--enable-shared=yes) shared=yes ;;
 154 --disable-shared|--enable-shared=no) shared=no ;;
 155 --enable-static|--enable-static=yes) static=yes ;;
 156 --disable-static|--enable-static=no) static=no ;;
 157 --enable-optimize) optimize=yes ;;
 158 --enable-optimize=*) optimize=${arg#*=} ;;
 159 --disable-optimize) optimize=no ;;
 160 --enable-debug|--enable-debug=yes) debug=yes ;;
 161 --disable-debug|--enable-debug=no) debug=no ;;
 162 --enable-warnings|--enable-warnings=yes) warnings=yes ;;
 163 --disable-warnings|--enable-warnings=no) warnings=no ;;
 164 --enable-wrapper|--enable-wrapper=yes) wrapper=detect ;;
 165 --enable-wrapper=all) wrapper=yes ; gcc_wrapper=yes ; clang_wrapper=yes ;;
 166 --enable-wrapper=gcc) wrapper=yes ; gcc_wrapper=yes ;;
 167 --enable-wrapper=clang) wrapper=yes ; clang_wrapper=yes ;;
 168 --disable-wrapper|--enable-wrapper=no) wrapper=no ;;
 169 --enable-gcc-wrapper|--enable-gcc-wrapper=yes) wrapper=yes ; gcc_wrapper=yes ;;
 170 --disable-gcc-wrapper|--enable-gcc-wrapper=no) wrapper=no ;;
 171 --enable-*|--disable-*|--with-*|--without-*|--*dir=*) ;;
 172 --host=*|--target=*) target=${arg#*=} ;;
 173 --build=*) build=${arg#*=} ;;
 174 -* ) echo "$0: unknown option $arg" ;;
 175 CC=*) CC=${arg#*=} ;;
 176 CFLAGS=*) CFLAGS=${arg#*=} ;;
 177 CPPFLAGS=*) CPPFLAGS=${arg#*=} ;;
 178 LDFLAGS=*) LDFLAGS=${arg#*=} ;;
 179 CROSS_COMPILE=*) CROSS_COMPILE=${arg#*=} ;;
 180 LIBCC=*) LIBCC=${arg#*=} ;;
 181 *=*) ;;
 182 *) build=$arg ; target=$arg ;;
 183 esac
 184 done
 185
 186 for i in srcdir prefix exec_prefix bindir libdir includedir syslibdir ; do
 187 stripdir $i
 188 done
 189
 190 #
 191 # Get the source dir for out-of-tree builds
 192 #
 193 if test -z "$srcdir" ; then
 194 srcdir="${0%/configure}"
 195 stripdir srcdir
 196 fi
 197 abs_builddir="$(pwd)" || fail "$0: cannot determine working directory"
 198 abs_srcdir="$(cd $srcdir && pwd)" || fail "$0: invalid source directory $srcdir"
 199 test "$abs_srcdir" = "$abs_builddir" && srcdir=.
 200 test "$srcdir" != "." -a -f Makefile -a ! -h Makefile && fail "$0: Makefile already exists in the working directory"
 201
 202 #
 203 # Get a temp filename we can use
 204 #
 205 i=0
 206 set -C
 207 while : ; do i=$(($i+1))
 208 tmpc="./conf$$-$PPID-$i.c"
 209 2>|/dev/null > "$tmpc" && break
 210 test "$i" -gt 50 && fail "$0: cannot create temporary file $tmpc"
 211 done
 212 set +C
 213 trap 'rm "$tmpc"' EXIT INT QUIT TERM HUP
 214
 215 #
 216 # Check whether we are cross-compiling, and set a default
 217 # CROSS_COMPILE prefix if none was provided.
 218 #
 219 test "$target" && \
 220 test "$target" != "$build" && \
 221 test -z "$CROSS_COMPILE" && \
 222 CROSS_COMPILE="$target-"
 223
 224 #
 225 # Find a C compiler to use
 226 #
 227 printf "checking for C compiler... "
 228 trycc ${CROSS_COMPILE}gcc
 229 trycc ${CROSS_COMPILE}c99
 230 trycc ${CROSS_COMPILE}cc
 231 printf "%s\n" "$CC"
 232 test -n "$CC" || { echo "$0: cannot find a C compiler" ; exit 1 ; }
 233
 234 printf "checking whether C compiler works... "
 235 echo "typedef int x;" > "$tmpc"
 236 if output=$($CC $CPPFLAGS $CFLAGS -c -o /dev/null "$tmpc" 2>&1) ; then
 237 printf "yes\n"
 238 else
 239 printf "no; compiler output follows:\n%s\n" "$output"
 240 exit 1
 241 fi
 242
 243 #
 244 # Figure out options to force errors on unknown flags.
 245 #
 246 tryflag   CFLAGS_TRY  -Werror=unknown-warning-option
 247 tryflag   CFLAGS_TRY  -Werror=unused-command-line-argument
 248 tryflag   CFLAGS_TRY  -Werror=ignored-optimization-argument
 249 tryldflag LDFLAGS_TRY -Werror=unknown-warning-option
 250 tryldflag LDFLAGS_TRY -Werror=unused-command-line-argument
 251
 252 #
 253 # Need to know if the compiler is gcc or clang to decide which toolchain
 254 # wrappers to build.
 255 #
 256 printf "checking for C compiler family... "
 257 cc_ver="$(LC_ALL=C $CC -v 2>&1)"
 258 cc_family=unknown
 259 if fnmatch '*gcc\ version*' "$cc_ver" ; then
 260 cc_family=gcc
 261 elif fnmatch '*clang\ version*' "$cc_ver" ; then
 262 cc_family=clang
 263 fi
 264 echo "$cc_family"
 265
 266 #
 267 # Figure out toolchain wrapper to build
 268 #
 269 if test "$wrapper" = auto -o "$wrapper" = detect ; then
 270 echo "#include <stdlib.h>" > "$tmpc"
 271 echo "#if ! __GLIBC__" >> "$tmpc"
 272 echo "#error no" >> "$tmpc"
 273 echo "#endif" >> "$tmpc"
 274 printf "checking for toolchain wrapper to build... "
 275 if test "$wrapper" = auto && ! $CC -c -o /dev/null "$tmpc" >/dev/null 2>&1 ; then
 276 echo "none"
 277 elif test "$cc_family" = gcc ; then
 278 gcc_wrapper=yes
 279 echo "gcc"
 280 elif test "$cc_family" = clang ; then
 281 clang_wrapper=yes
 282 echo "clang"
 283 else
 284 echo "none"
 285 if test "$wrapper" = detect ; then
 286 fail "$0: could not find an appropriate toolchain wrapper"
 287 fi
 288 fi
 289 fi
 290
 291 if test "$gcc_wrapper" = yes ; then
 292 tools="$tools obj/musl-gcc"
 293 tool_libs="$tool_libs lib/musl-gcc.specs"
 294 fi
 295 if test "$clang_wrapper" = yes ; then
 296 tools="$tools obj/musl-clang obj/ld.musl-clang"
 297 fi
 298
 299 #
 300 # Find the target architecture
 301 #
 302 printf "checking target system type... "
 303 test -n "$target" || target=$($CC -dumpmachine 2>/dev/null) || target=unknown
 304 printf "%s\n" "$target"
 305
 306 #
 307 # Convert to just ARCH
 308 #
 309 case "$target" in
 310 # Catch these early to simplify matching for 32-bit archs
 311 arm*) ARCH=arm ;;
 312 aarch64*) ARCH=aarch64 ;;
 313 i?86-nt32*) ARCH=nt32 ;;
 314 i?86*) ARCH=i386 ;;
 315 x86_64-x32*|x32*|x86_64*x32) ARCH=x32 ;;
 316 x86_64-nt64*) ARCH=nt64 ;;
 317 x86_64*) ARCH=x86_64 ;;
 318 m68k*) ARCH=m68k ;;
 319 mips64*|mipsisa64*) ARCH=mips64 ;;
 320 mips*) ARCH=mips ;;
 321 microblaze*) ARCH=microblaze ;;
 322 or1k*) ARCH=or1k ;;
 323 powerpc64*) ARCH=powerpc64 ;;
 324 powerpc*) ARCH=powerpc ;;
 325 sh[1-9bel-]*|sh|superh*) ARCH=sh ;;
 326 s390x*) ARCH=s390x ;;
 327 unknown) fail "$0: unable to detect target arch; try $0 --target=..." ;;
 328 *) fail "$0: unknown or unsupported target \"$target\"" ;;
 329 esac
 330
 331 #
 332 # Try to get a conforming C99 freestanding environment
 333 #
 334 tryflag CFLAGS_C99FSE -std=c99
 335 tryflag CFLAGS_C99FSE -nostdinc
 336 tryflag CFLAGS_C99FSE -ffreestanding \
 337 || tryflag CFLAGS_C99FSE -fno-builtin
 338 tryflag CFLAGS_C99FSE -fexcess-precision=standard \
 339 || { test "$ARCH" = i386 && tryflag CFLAGS_C99FSE -ffloat-store ; }
 340 tryflag CFLAGS_C99FSE -frounding-math
 341
 342 #
 343 # We may use the may_alias attribute if __GNUC__ is defined, so
 344 # if the compiler defines __GNUC__ but does not provide it,
 345 # it must be defined away as part of the CFLAGS.
 346 #
 347 printf "checking whether compiler needs attribute((may_alias)) suppression... "
 348 cat > "$tmpc" <<EOF
 349 typedef int
 350 #ifdef __GNUC__
 351 __attribute__((__may_alias__))
 352 #endif
 353 x;
 354 EOF
 355 if $CC $CFLAGS_C99FSE $CPPFLAGS $CFLAGS \
 356   -c -o /dev/null "$tmpc" >/dev/null 2>&1 ; then
 357 printf "no\n"
 358 else
 359 printf "yes\n"
 360 CFLAGS_C99FSE="$CFLAGS_C99FSE -D__may_alias__="
 361 fi
 362
 363 #
 364 # The GNU toolchain defaults to assuming unmarked files need an
 365 # executable stack, potentially exposing vulnerabilities in programs
 366 # linked with such object files. Fix this.
 367 #
 368 tryflag CFLAGS_C99FSE -Wa,--noexecstack
 369
 370 #
 371 # Check for options to disable stack protector, which needs to be
 372 # disabled for a few early-bootstrap translation units. If not found,
 373 # this is not an error; we assume the toolchain does not do ssp.
 374 #
 375 tryflag CFLAGS_NOSSP -fno-stack-protector
 376
 377 #
 378 # Check for options that may be needed to prevent the compiler from
 379 # generating self-referential versions of memcpy,, memmove, memcmp,
 380 # and memset. Really, we should add a check to determine if this
 381 # option is sufficient, and if not, add a macro to cripple these
 382 # functions with volatile...
 383 #
 384 tryflag CFLAGS_MEMOPS -fno-tree-loop-distribute-patterns
 385
 386 #
 387 # Enable debugging if requessted.
 388 #
 389 test "$debug" = yes && CFLAGS_AUTO=-g
 390
 391 #
 392 # Preprocess asm files to add extra debugging information if debug is
 393 # enabled, our assembler supports the needed directives, and the
 394 # preprocessing script has been written for our architecture.
 395 #
 396 printf "checking whether we should preprocess assembly to add debugging information... "
 397 if fnmatch '-g*|*\ -g*' "$CFLAGS_AUTO $CFLAGS" &&
 398    test -f "tools/add-cfi.$ARCH.awk" &&
 399    printf ".file 1 \"srcfile.s\"\n.line 1\n.cfi_startproc\n.cfi_endproc" | $CC -g -x assembler -c -o /dev/null 2>/dev/null -
 400 then
 401   ADD_CFI=yes
 402 else
 403   ADD_CFI=no
 404 fi
 405 printf "%s\n" "$ADD_CFI"
 406
 407 #
 408 # Possibly add a -O option to CFLAGS and select modules to optimize with
 409 # -O3 based on the status of --enable-optimize and provided CFLAGS.
 410 #
 411 printf "checking for optimization settings... "
 412 case "x$optimize" in
 413 xauto)
 414 if fnmatch '-O*|*\ -O*' "$CFLAGS_AUTO $CFLAGS" ; then
 415 printf "using provided CFLAGS\n" ;optimize=no
 416 else
 417 printf "using defaults\n" ; optimize=yes
 418 fi
 419 ;;
 420 xsize|xnone) printf "minimize size\n" ; optimize=size ;;
 421 xno|x) printf "disabled\n" ; optimize=no ;;
 422 *) printf "custom\n" ;;
 423 esac
 424
 425 test "$optimize" = no || tryflag CFLAGS_AUTO -Os || tryflag CFLAGS_AUTO -O2
 426 test "$optimize" = yes && optimize="internal,malloc,string"
 427
 428 if fnmatch 'no|size' "$optimize" ; then :
 429 else
 430 printf "components to be optimized for speed:"
 431 while test "$optimize" ; do
 432 case "$optimize" in
 433 *,*) this=${optimize%%,*} optimize=${optimize#*,} ;;
 434 *) this=$optimize optimize=
 435 esac
 436 printf " $this"
 437 case "$this" in
 438 */*.c) ;;
 439 */*) this=$this*.c ;;
 440 *) this=$this/*.c ;;
 441 esac
 442 OPTIMIZE_GLOBS="$OPTIMIZE_GLOBS $this"
 443 done
 444 OPTIMIZE_GLOBS=${OPTIMIZE_GLOBS# }
 445 printf "\n"
 446 fi
 447
 448 # Always try -pipe
 449 tryflag CFLAGS_AUTO -pipe
 450
 451 #
 452 # If debugging is disabled, omit frame pointer. Modern GCC does this
 453 # anyway on most archs even when debugging is enabled since the frame
 454 # pointer is no longer needed for debugging.
 455 #
 456 if fnmatch '-g*|*\ -g*' "$CFLAGS_AUTO $CFLAGS" ; then :
 457 else
 458 tryflag CFLAGS_AUTO -fomit-frame-pointer
 459 fi
 460
 461 #
 462 # Modern GCC wants to put DWARF tables (used for debugging and
 463 # unwinding) in the loaded part of the program where they are
 464 # unstrippable. These options force them back to debug sections (and
 465 # cause them not to get generated at all if debugging is off).
 466 #
 467 tryflag CFLAGS_AUTO -fno-unwind-tables
 468 tryflag CFLAGS_AUTO -fno-asynchronous-unwind-tables
 469
 470 #
 471 # Attempt to put each function and each data object in its own
 472 # section. This both allows additional size optimizations at link
 473 # time and works around a dangerous class of compiler/assembler bugs
 474 # whereby relative address expressions are constant-folded by the
 475 # assembler even when one or more of the symbols involved is
 476 # replaceable. See gas pr 18561 and gcc pr 66609, 68178, etc.
 477 #
 478 tryflag CFLAGS_AUTO -ffunction-sections
 479 tryflag CFLAGS_AUTO -fdata-sections
 480
 481 #
 482 # On x86, make sure we don't have incompatible instruction set
 483 # extensions enabled by default. This is bad for making static binaries.
 484 # We cheat and use i486 rather than i386 because i386 really does not
 485 # work anyway (issues with atomic ops).
 486 # Some build environments pass -march and -mtune options via CC, so
 487 # check both CC and CFLAGS.
 488 #
 489 if test "$ARCH" = "i386" ; then
 490 fnmatch '-march=*|*\ -march=*' "$CC $CFLAGS" || tryldflag CFLAGS_AUTO -march=i486
 491 fnmatch '-mtune=*|*\ -mtune=*' "$CC $CFLAGS" || tryldflag CFLAGS_AUTO -mtune=generic
 492 fi
 493
 494 #
 495 # Even with -std=c99, gcc accepts some constructs which are constraint
 496 # violations. We want to treat these as errors regardless of whether
 497 # other purely stylistic warnings are enabled -- especially implicit
 498 # function declarations, which are a dangerous programming error.
 499 #
 500 tryflag CFLAGS_AUTO -Werror=implicit-function-declaration
 501 tryflag CFLAGS_AUTO -Werror=implicit-int
 502 tryflag CFLAGS_AUTO -Werror=pointer-sign
 503 tryflag CFLAGS_AUTO -Werror=pointer-arith
 504
 505 #
 506 # GCC ignores unused arguements by default, but Clang needs this extra
 507 # parameter to stop printing warnings about LDFLAGS passed during
 508 # compiling stage and CFLAGS passed during linking stage.
 509 #
 510 test "$cc_family" = clang && tryflag CFLAGS_AUTO -Qunused-arguments
 511
 512 if test "x$warnings" = xyes ; then
 513 tryflag CFLAGS_AUTO -Wall
 514 tryflag CFLAGS_AUTO -Wno-parentheses
 515 tryflag CFLAGS_AUTO -Wno-uninitialized
 516 tryflag CFLAGS_AUTO -Wno-missing-braces
 517 tryflag CFLAGS_AUTO -Wno-unused-value
 518 tryflag CFLAGS_AUTO -Wno-unused-but-set-variable
 519 tryflag CFLAGS_AUTO -Wno-unknown-pragmas
 520 tryflag CFLAGS_AUTO -Wno-pointer-to-int-cast
 521 fi
 522
 523 # Determine if the compiler produces position-independent code (PIC)
 524 # by default. If so, we don't need to compile separate object files
 525 # for libc.a and libc.so.
 526 if trycppif __PIC__ "$CFLAGS_C99FSE $CPPFLAGS $CFLAGS" ; then
 527 pic_default=yes
 528 else
 529 pic_default=no
 530 fi
 531
 532 # Reduce space lost to padding for alignment purposes by sorting data
 533 # objects according to their alignment reqirements. This approximates
 534 # optimal packing.
 535 tryldflag LDFLAGS_AUTO -Wl,--sort-section,alignment
 536 tryldflag LDFLAGS_AUTO -Wl,--sort-common
 537
 538 # When linking shared library, drop dummy weak definitions that were
 539 # replaced by strong definitions from other translation units.
 540 tryldflag LDFLAGS_AUTO -Wl,--gc-sections
 541
 542 # Some patched GCC builds have these defaults messed up...
 543 tryldflag LDFLAGS_AUTO -Wl,--hash-style=both
 544
 545 # Prevent linking if there are undefined symbols; if any exist,
 546 # libc.so will crash at runtime during relocation processing.
 547 # The common way this can happen is failure to link the compiler
 548 # runtime library; implementation error is also a possibility.
 549 tryldflag LDFLAGS_AUTO -Wl,--no-undefined
 550
 551 # Avoid exporting symbols from compiler runtime libraries. They
 552 # should be hidden anyway, but some toolchains including old gcc
 553 # versions built without shared library support and pcc are broken.
 554 tryldflag LDFLAGS_AUTO -Wl,--exclude-libs=ALL
 555
 556 # Public data symbols must be interposable to allow for copy
 557 # relocations, but otherwise we want to bind symbols at libc link
 558 # time to eliminate startup relocations and PLT overhead. Use
 559 # --dynamic-list rather than -Bsymbolic-functions for greater
 560 # control over what symbols are left unbound.
 561 tryldflag LDFLAGS_AUTO -Wl,--dynamic-list="$srcdir/dynamic.list"
 562
 563 # Find compiler runtime library
 564 test -z "$LIBCC" && tryldflag LIBCC -lgcc && tryldflag LIBCC -lgcc_eh
 565 test -z "$LIBCC" && tryldflag LIBCC -lcompiler_rt
 566 test -z "$LIBCC" && try_libcc=`$CC -print-libgcc-file-name 2>/dev/null` \
 567                  && tryldflag LIBCC "$try_libcc"
 568 test -z "$LIBCC" && try_libcc=`$CC -print-file-name=libpcc.a 2>/dev/null` \
 569                  && tryldflag LIBCC "$try_libcc"
 570 printf "using compiler runtime libraries: %s\n" "$LIBCC"
 571
 572 # Figure out arch variants for archs with variants
 573 SUBARCH=
 574 t="$CFLAGS_C99FSE $CPPFLAGS $CFLAGS"
 575
 576 if test "$ARCH" = "x86_64" ; then
 577 trycppif __ILP32__ "$t" && ARCH=x32
 578 fi
 579
 580 if test "$ARCH" = "arm" ; then
 581 if trycppif __thumb2__ "$t" ; then
 582 tryflag CFLAGS_AUTO -mimplicit-it=always
 583 tryflag CFLAGS_AUTO -Wa,-mimplicit-it=always
 584 tryflag CFLAGS_AUTO -Wa,-mthumb
 585 fi
 586 trycppif __ARMEB__ "$t" && SUBARCH=${SUBARCH}eb
 587 trycppif __ARM_PCS_VFP "$t" && SUBARCH=${SUBARCH}hf
 588 # Versions of clang up until at least 3.8 have the wrong constraint codes
 589 # for floating point operands to inline asm. Detect this so the affected
 590 # source files can just disable the asm.
 591 if test "$cc_family" = clang ; then
 592 printf "checking whether clang's vfp asm constraints work... "
 593 echo 'float f(float x) { __asm__("":"+t"(x)); return x; }' > "$tmpc"
 594 if $CC $CFLAGS_C99FSE $CPPFLAGS $CFLAGS -c -o /dev/null "$tmpc" >/dev/null 2>&1 ; then
 595 printf "yes\n"
 596 else
 597 printf "no\n"
 598 CFLAGS_AUTO="$CFLAGS_AUTO -DBROKEN_VFP_ASM"
 599 CFLAGS_AUTO="${CFLAGS_AUTO# }"
 600 fi
 601 fi
 602 fi
 603
 604 if test "$ARCH" = "aarch64" ; then
 605 trycppif __AARCH64EB__ "$t" && SUBARCH=${SUBARCH}_be
 606 fi
 607
 608 if test "$ARCH" = "m68k" ; then
 609 if trycppif "__HAVE_68881__" ; then : ;
 610 elif trycppif "__mcffpu__" ; then SUBARCH="-fp64"
 611 else SUBARCH="-sf"
 612 fi
 613 fi
 614
 615 if test "$ARCH" = "mips" ; then
 616 trycppif "__mips_isa_rev >= 6" "$t" && SUBARCH=${SUBARCH}r6
 617 trycppif "_MIPSEL || __MIPSEL || __MIPSEL__" "$t" && SUBARCH=${SUBARCH}el
 618 trycppif __mips_soft_float "$t" && SUBARCH=${SUBARCH}-sf
 619 fi
 620
 621 if test "$ARCH" = "mips64" ; then
 622 trycppif "_MIPS_SIM != _ABI64" "$t" && ARCH=mipsn32
 623 trycppif "__mips_isa_rev >= 6" "$t" && SUBARCH=${SUBARCH}r6
 624 trycppif "_MIPSEL || __MIPSEL || __MIPSEL__" "$t" && SUBARCH=${SUBARCH}el
 625 trycppif __mips_soft_float "$t" && SUBARCH=${SUBARCH}-sf
 626 fi
 627
 628 if test "$ARCH" = "powerpc" ; then
 629 trycppif "__NO_FPRS__ && !_SOFT_FLOAT" "$t" && fail \
 630   "$0: error: compiler's floating point configuration is unsupported"
 631 trycppif _SOFT_FLOAT "$t" && SUBARCH=${SUBARCH}-sf
 632 fi
 633
 634 test "$ARCH" = "microblaze" && trycppif __MICROBLAZEEL__ "$t" \
 635 && SUBARCH=${SUBARCH}el
 636
 637 if test "$ARCH" = "powerpc64" ; then
 638 trycppif "_CALL_ELF == 2" "$t" || fail "$0: error: unsupported powerpc64 ABI"
 639 trycppif __LITTLE_ENDIAN__ "$t" && SUBARCH=${SUBARCH}le
 640 trycppif _SOFT_FLOAT "$t" && fail "$0: error: soft-float not supported on powerpc64"
 641 fi
 642
 643 if test "$ARCH" = "sh" ; then
 644 tryflag CFLAGS_AUTO -Wa,--isa=any
 645 trycppif __BIG_ENDIAN__ "$t" && SUBARCH=${SUBARCH}eb
 646 if trycppif "__SH_FPU_ANY__ || __SH4__" "$t" ; then
 647 # Some sh configurations are broken and replace double with float
 648 # rather than using softfloat when the fpu is present but only
 649 # supports single precision. Reject them.
 650 printf "checking whether compiler's double type is IEEE double... "
 651 echo 'typedef char dblcheck[(int)sizeof(double)-5];' > "$tmpc"
 652 if $CC $CFLAGS_C99FSE $CPPFLAGS $CFLAGS -c -o /dev/null "$tmpc" >/dev/null 2>&1 ; then
 653 printf "yes\n"
 654 else
 655 printf "no\n"
 656 fail "$0: error: compiler's floating point configuration is unsupported"
 657 fi
 658 else
 659 SUBARCH=${SUBARCH}-nofpu
 660 fi
 661 if trycppif __SH_FDPIC__ "$t" ; then
 662 SUBARCH=${SUBARCH}-fdpic
 663 fi
 664 fi
 665
 666 test "$SUBARCH" \
 667 && printf "configured for %s variant: %s\n" "$ARCH" "$ARCH$SUBARCH"
 668
 669 case "$ARCH$SUBARCH" in
 670 arm) ASMSUBARCH=el ;;
 671 *) ASMSUBARCH=$SUBARCH ;;
 672 esac
 673
 674 #
 675 # Some archs (powerpc) have different possible long double formats
 676 # that the compiler can be configured for. The logic for whether this
 677 # is supported is in bits/float.h; in general, it is not. We need to
 678 # check for mismatches here or code in printf, strotd, and scanf will
 679 # be dangerously incorrect because it depends on (1) the macros being
 680 # correct, and (2) IEEE semantics.
 681 #
 682 printf "checking whether compiler's long double definition matches float.h... "
 683 echo '#include <float.h>' > "$tmpc"
 684 echo '#define C(m,s) (m==LDBL_MANT_DIG && s==sizeof(long double))' >> "$tmpc"
 685 echo 'typedef char ldcheck[(C(53,8)||C(64,12)||C(64,16)||C(113,16))*2-1];' >> "$tmpc"
 686 if $CC $CFLAGS_C99FSE \
 687   -I$srcdir/arch/$ARCH -I$srcdir/arch/generic -I$srcdir/include \
 688   $CPPFLAGS $CFLAGS -c -o /dev/null "$tmpc" >/dev/null 2>&1 ; then
 689 printf "yes\n"
 690 else
 691 printf "no\n"
 692 fail "$0: error: unsupported long double type"
 693 fi
 694
 695 #
 696 # Some build systems globally pass in broken CFLAGS like -ffast-math
 697 # for all packages. On recent GCC we can detect this and error out
 698 # early rather than producing a seriously-broken math library.
 699 #
 700 if trycppif "__FAST_MATH__" \
 701   "$CFLAGS_C99FSE $CPPFLAGS $CFLAGS" ; then
 702 fail "$0: error: compiler has broken floating point; check CFLAGS"
 703 fi
 704
 705 printf "creating config.mak... "
 706
 707 cmdline=$(quote "$0")
 708 for i ; do cmdline="$cmdline $(quote "$i")" ; done
 709
 710 exec 3>&1 1>config.mak
 711
 712
 713 cat << EOF
 714 # This version of config.mak was generated by:
 715 # $cmdline
 716 # Any changes made here will be lost if configure is re-run
 717 ARCH = $ARCH
 718 SUBARCH = $SUBARCH
 719 ASMSUBARCH = $ASMSUBARCH
 720 srcdir = $srcdir
 721 prefix = $prefix
 722 exec_prefix = $exec_prefix
 723 bindir = $bindir
 724 libdir = $libdir
 725 includedir = $includedir
 726 syslibdir = $syslibdir
 727 CC = $CC
 728 CFLAGS = $CFLAGS
 729 CFLAGS_AUTO = $CFLAGS_AUTO
 730 CFLAGS_C99FSE = $CFLAGS_C99FSE
 731 CFLAGS_MEMOPS = $CFLAGS_MEMOPS
 732 CFLAGS_NOSSP = $CFLAGS_NOSSP
 733 CPPFLAGS = $CPPFLAGS
 734 LDFLAGS = $LDFLAGS
 735 LDFLAGS_AUTO = $LDFLAGS_AUTO
 736 CROSS_COMPILE = $CROSS_COMPILE
 737 LIBCC = $LIBCC
 738 OPTIMIZE_GLOBS = $OPTIMIZE_GLOBS
 739 ALL_TOOLS = $tools
 740 TOOL_LIBS = $tool_libs
 741 ADD_CFI = $ADD_CFI
 742 EOF
 743 test "x$static" = xno && echo "STATIC_LIBS ="
 744 test "x$shared" = xno && echo "SHARED_LIBS ="
 745 test "x$cc_family" = xgcc && echo 'WRAPCC_GCC = $(CC)'
 746 test "x$cc_family" = xclang && echo 'WRAPCC_CLANG = $(CC)'
 747 test "x$pic_default" = xyes && echo 'AOBJS = $(LOBJS)'
 748 exec 1>&3 3>&-
 749
 750 test "$srcdir" = "." || ln -sf $srcdir/Makefile .
 751
 752 printf "done\n"