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-visibility     use global visibility options to optimize PIC [auto]
  35   --enable-wrapper=...    build given musl toolchain wrapper [auto]
  36   --disable-shared        inhibit building shared library [enabled]
  37   --disable-static        inhibit building static library [enabled]
  38
  39 Some influential environment variables:
  40   CC                      C compiler command [detected]
  41   CFLAGS                  C compiler flags [-Os -pipe ...]
  42   CROSS_COMPILE           prefix for cross compiler and tools [none]
  43   LIBCC                   compiler runtime library [detected]
  44
  45 Use these variables to override the choices made by configure.
  46
  47 EOF
  48 exit 0
  49 }
  50
  51 # Helper functions
  52
  53 quote () {
  54 tr '\n' ' ' <<EOF | grep '^[-[:alnum:]_=,./:]* $' >/dev/null 2>&1 && { echo "$1" ; return 0 ; }
  55 $1
  56 EOF
  57 printf %s\\n "$1" | sed -e "s/'/'\\\\''/g" -e "1s/^/'/" -e "\$s/\$/'/" -e "s#^'\([-[:alnum:]_,./:]*\)=\(.*\)\$#\1='\2#"
  58 }
  59 echo () { printf "%s\n" "$*" ; }
  60 fail () { echo "$*" ; exit 1 ; }
  61 fnmatch () { eval "case \"\$2\" in $1) return 0 ;; *) return 1 ;; esac" ; }
  62 cmdexists () { type "$1" >/dev/null 2>&1 ; }
  63 trycc () { test -z "$CC" && cmdexists "$1" && CC=$1 ; }
  64
  65 stripdir () {
  66 while eval "fnmatch '*/' \"\${$1}\"" ; do eval "$1=\${$1%/}" ; done
  67 }
  68
  69 trycppif () {
  70 printf "checking preprocessor condition %s... " "$1"
  71 echo "typedef int x;" > "$tmpc"
  72 echo "#if $1" >> "$tmpc"
  73 echo "#error yes" >> "$tmpc"
  74 echo "#endif" >> "$tmpc"
  75 if $CC $2 -c -o /dev/null "$tmpc" >/dev/null 2>&1 ; then
  76 printf "false\n"
  77 return 1
  78 else
  79 printf "true\n"
  80 return 0
  81 fi
  82 }
  83
  84 tryflag () {
  85 printf "checking whether compiler accepts %s... " "$2"
  86 echo "typedef int x;" > "$tmpc"
  87 if $CC $CFLAGS_TRY $2 -c -o /dev/null "$tmpc" >/dev/null 2>&1 ; then
  88 printf "yes\n"
  89 eval "$1=\"\${$1} \$2\""
  90 eval "$1=\${$1# }"
  91 return 0
  92 else
  93 printf "no\n"
  94 return 1
  95 fi
  96 }
  97
  98 tryldflag () {
  99 printf "checking whether linker accepts %s... " "$2"
 100 echo "typedef int x;" > "$tmpc"
 101 if $CC $LDFLAGS_TRY -nostdlib -shared "$2" -o /dev/null "$tmpc" >/dev/null 2>&1 ; then
 102 printf "yes\n"
 103 eval "$1=\"\${$1} \$2\""
 104 eval "$1=\${$1# }"
 105 return 0
 106 else
 107 printf "no\n"
 108 return 1
 109 fi
 110 }
 111
 112
 113
 114 # Beginning of actual script
 115
 116 CFLAGS_C99FSE=
 117 CFLAGS_AUTO=
 118 CFLAGS_MEMOPS=
 119 CFLAGS_NOSSP=
 120 CFLAGS_TRY=
 121 LDFLAGS_AUTO=
 122 LDFLAGS_TRY=
 123 OPTIMIZE_GLOBS=
 124 srcdir=
 125 prefix=/usr/local/musl
 126 exec_prefix='$(prefix)'
 127 bindir='$(exec_prefix)/bin'
 128 libdir='$(prefix)/lib'
 129 includedir='$(prefix)/include'
 130 syslibdir='/lib'
 131 tools=
 132 tool_libs=
 133 build=
 134 target=
 135 optimize=auto
 136 debug=no
 137 warnings=no
 138 visibility=auto
 139 shared=auto
 140 static=yes
 141 wrapper=auto
 142 gcc_wrapper=no
 143 clang_wrapper=no
 144
 145 for arg ; do
 146 case "$arg" in
 147 --help|-h) usage ;;
 148 --srcdir=*) srcdir=${arg#*=} ;;
 149 --prefix=*) prefix=${arg#*=} ;;
 150 --exec-prefix=*) exec_prefix=${arg#*=} ;;
 151 --bindir=*) bindir=${arg#*=} ;;
 152 --libdir=*) libdir=${arg#*=} ;;
 153 --includedir=*) includedir=${arg#*=} ;;
 154 --syslibdir=*) syslibdir=${arg#*=} ;;
 155 --enable-shared|--enable-shared=yes) shared=yes ;;
 156 --disable-shared|--enable-shared=no) shared=no ;;
 157 --enable-static|--enable-static=yes) static=yes ;;
 158 --disable-static|--enable-static=no) static=no ;;
 159 --enable-optimize) optimize=yes ;;
 160 --enable-optimize=*) optimize=${arg#*=} ;;
 161 --disable-optimize) optimize=no ;;
 162 --enable-debug|--enable-debug=yes) debug=yes ;;
 163 --disable-debug|--enable-debug=no) debug=no ;;
 164 --enable-warnings|--enable-warnings=yes) warnings=yes ;;
 165 --disable-warnings|--enable-warnings=no) warnings=no ;;
 166 --enable-visibility|--enable-visibility=yes) visibility=yes ;;
 167 --disable-visibility|--enable-visibility=no) visibility=no ;;
 168 --enable-wrapper|--enable-wrapper=yes) wrapper=detect ;;
 169 --enable-wrapper=all) wrapper=yes ; gcc_wrapper=yes ; clang_wrapper=yes ;;
 170 --enable-wrapper=gcc) wrapper=yes ; gcc_wrapper=yes ;;
 171 --enable-wrapper=clang) wrapper=yes ; clang_wrapper=yes ;;
 172 --disable-wrapper|--enable-wrapper=no) wrapper=no ;;
 173 --enable-gcc-wrapper|--enable-gcc-wrapper=yes) wrapper=yes ; gcc_wrapper=yes ;;
 174 --disable-gcc-wrapper|--enable-gcc-wrapper=no) wrapper=no ;;
 175 --enable-*|--disable-*|--with-*|--without-*|--*dir=*) ;;
 176 --host=*|--target=*) target=${arg#*=} ;;
 177 --build=*) build=${arg#*=} ;;
 178 -* ) echo "$0: unknown option $arg" ;;
 179 CC=*) CC=${arg#*=} ;;
 180 CFLAGS=*) CFLAGS=${arg#*=} ;;
 181 CPPFLAGS=*) CPPFLAGS=${arg#*=} ;;
 182 LDFLAGS=*) LDFLAGS=${arg#*=} ;;
 183 CROSS_COMPILE=*) CROSS_COMPILE=${arg#*=} ;;
 184 LIBCC=*) LIBCC=${arg#*=} ;;
 185 *=*) ;;
 186 *) build=$arg ; target=$arg ;;
 187 esac
 188 done
 189
 190 for i in srcdir prefix exec_prefix bindir libdir includedir syslibdir ; do
 191 stripdir $i
 192 done
 193
 194 #
 195 # Get the source dir for out-of-tree builds
 196 #
 197 if test -z "$srcdir" ; then
 198 srcdir="${0%/configure}"
 199 stripdir srcdir
 200 fi
 201 abs_builddir="$(pwd)" || fail "$0: cannot determine working directory"
 202 abs_srcdir="$(cd $srcdir && pwd)" || fail "$0: invalid source directory $srcdir"
 203 test "$abs_srcdir" = "$abs_builddir" && srcdir=.
 204 test "$srcdir" != "." -a -f Makefile -a ! -h Makefile && fail "$0: Makefile already exists in the working directory"
 205
 206 #
 207 # Get a temp filename we can use
 208 #
 209 i=0
 210 set -C
 211 while : ; do i=$(($i+1))
 212 tmpc="./conf$$-$PPID-$i.c"
 213 2>|/dev/null > "$tmpc" && break
 214 test "$i" -gt 50 && fail "$0: cannot create temporary file $tmpc"
 215 done
 216 set +C
 217 trap 'rm "$tmpc"' EXIT INT QUIT TERM HUP
 218
 219 #
 220 # Check whether we are cross-compiling, and set a default
 221 # CROSS_COMPILE prefix if none was provided.
 222 #
 223 test "$target" && \
 224 test "$target" != "$build" && \
 225 test -z "$CROSS_COMPILE" && \
 226 CROSS_COMPILE="$target-"
 227
 228 #
 229 # Find a C compiler to use
 230 #
 231 printf "checking for C compiler... "
 232 trycc ${CROSS_COMPILE}gcc
 233 trycc ${CROSS_COMPILE}c99
 234 trycc ${CROSS_COMPILE}cc
 235 printf "%s\n" "$CC"
 236 test -n "$CC" || { echo "$0: cannot find a C compiler" ; exit 1 ; }
 237
 238 printf "checking whether C compiler works... "
 239 echo "typedef int x;" > "$tmpc"
 240 if output=$($CC $CPPFLAGS $CFLAGS -c -o /dev/null "$tmpc" 2>&1) ; then
 241 printf "yes\n"
 242 else
 243 printf "no; compiler output follows:\n%s\n" "$output"
 244 exit 1
 245 fi
 246
 247 #
 248 # Figure out options to force errors on unknown flags.
 249 #
 250 tryflag   CFLAGS_TRY  -Werror=unknown-warning-option
 251 tryflag   CFLAGS_TRY  -Werror=unused-command-line-argument
 252 tryflag   CFLAGS_TRY  -Werror=ignored-optimization-argument
 253 tryldflag LDFLAGS_TRY -Werror=unknown-warning-option
 254 tryldflag LDFLAGS_TRY -Werror=unused-command-line-argument
 255
 256 #
 257 # Need to know if the compiler is gcc or clang to decide which toolchain
 258 # wrappers to build.
 259 #
 260 printf "checking for C compiler family... "
 261 cc_ver="$(LC_ALL=C $CC -v 2>&1)"
 262 cc_family=unknown
 263 if fnmatch '*gcc\ version*' "$cc_ver" ; then
 264 cc_family=gcc
 265 elif fnmatch '*clang\ version*' "$cc_ver" ; then
 266 cc_family=clang
 267 fi
 268 echo "$cc_family"
 269
 270 #
 271 # Figure out toolchain wrapper to build
 272 #
 273 if test "$wrapper" = auto -o "$wrapper" = detect ; then
 274 echo "#include <stdlib.h>" > "$tmpc"
 275 echo "#if ! __GLIBC__" >> "$tmpc"
 276 echo "#error no" >> "$tmpc"
 277 echo "#endif" >> "$tmpc"
 278 printf "checking for toolchain wrapper to build... "
 279 if test "$wrapper" = auto && ! $CC -c -o /dev/null "$tmpc" >/dev/null 2>&1 ; then
 280 echo "none"
 281 elif test "$cc_family" = gcc ; then
 282 gcc_wrapper=yes
 283 echo "gcc"
 284 elif test "$cc_family" = clang ; then
 285 clang_wrapper=yes
 286 echo "clang"
 287 else
 288 echo "none"
 289 if test "$wrapper" = detect ; then
 290 fail "$0: could not find an appropriate toolchain wrapper"
 291 fi
 292 fi
 293 fi
 294
 295 if test "$gcc_wrapper" = yes ; then
 296 tools="$tools obj/musl-gcc"
 297 tool_libs="$tool_libs lib/musl-gcc.specs"
 298 fi
 299 if test "$clang_wrapper" = yes ; then
 300 tools="$tools obj/musl-clang obj/ld.musl-clang"
 301 fi
 302
 303 #
 304 # Find the target architecture
 305 #
 306 printf "checking target system type... "
 307 test -n "$target" || target=$($CC -dumpmachine 2>/dev/null) || target=unknown
 308 printf "%s\n" "$target"
 309
 310 #
 311 # Convert to just ARCH
 312 #
 313 case "$target" in
 314 # Catch these early to simplify matching for 32-bit archs
 315 arm*) ARCH=arm ;;
 316 aarch64*) ARCH=aarch64 ;;
 317 i?86-nt32*) ARCH=nt32 ;;
 318 i?86*) ARCH=i386 ;;
 319 x86_64-x32*|x32*|x86_64*x32) ARCH=x32 ;;
 320 x86_64-nt64*) ARCH=nt64 ;;
 321 x86_64*) ARCH=x86_64 ;;
 322 mips64*|mipsisa64*) ARCH=mips64 ;;
 323 mips*) ARCH=mips ;;
 324 microblaze*) ARCH=microblaze ;;
 325 or1k*) ARCH=or1k ;;
 326 powerpc64*) ARCH=powerpc64 ;;
 327 powerpc*) ARCH=powerpc ;;
 328 sh[1-9bel-]*|sh|superh*) ARCH=sh ;;
 329 s390x*) ARCH=s390x ;;
 330 unknown) fail "$0: unable to detect target arch; try $0 --target=..." ;;
 331 *) fail "$0: unknown or unsupported target \"$target\"" ;;
 332 esac
 333
 334 #
 335 # Try to get a conforming C99 freestanding environment
 336 #
 337 tryflag CFLAGS_C99FSE -std=c99
 338 tryflag CFLAGS_C99FSE -nostdinc
 339 tryflag CFLAGS_C99FSE -ffreestanding \
 340 || tryflag CFLAGS_C99FSE -fno-builtin
 341 tryflag CFLAGS_C99FSE -fexcess-precision=standard \
 342 || { test "$ARCH" = i386 && tryflag CFLAGS_C99FSE -ffloat-store ; }
 343 tryflag CFLAGS_C99FSE -frounding-math
 344
 345 #
 346 # We may use the may_alias attribute if __GNUC__ is defined, so
 347 # if the compiler defines __GNUC__ but does not provide it,
 348 # it must be defined away as part of the CFLAGS.
 349 #
 350 printf "checking whether compiler needs attribute((may_alias)) suppression... "
 351 cat > "$tmpc" <<EOF
 352 typedef int
 353 #ifdef __GNUC__
 354 __attribute__((__may_alias__))
 355 #endif
 356 x;
 357 EOF
 358 if $CC $CFLAGS_C99FSE $CPPFLAGS $CFLAGS \
 359   -c -o /dev/null "$tmpc" >/dev/null 2>&1 ; then
 360 printf "no\n"
 361 else
 362 printf "yes\n"
 363 CFLAGS_C99FSE="$CFLAGS_C99FSE -D__may_alias__="
 364 fi
 365
 366 #
 367 # The GNU toolchain defaults to assuming unmarked files need an
 368 # executable stack, potentially exposing vulnerabilities in programs
 369 # linked with such object files. Fix this.
 370 #
 371 tryflag CFLAGS_C99FSE -Wa,--noexecstack
 372
 373 #
 374 # Check for options to disable stack protector, which needs to be
 375 # disabled for a few early-bootstrap translation units. If not found,
 376 # this is not an error; we assume the toolchain does not do ssp.
 377 #
 378 tryflag CFLAGS_NOSSP -fno-stack-protector
 379
 380 #
 381 # Check for options that may be needed to prevent the compiler from
 382 # generating self-referential versions of memcpy,, memmove, memcmp,
 383 # and memset. Really, we should add a check to determine if this
 384 # option is sufficient, and if not, add a macro to cripple these
 385 # functions with volatile...
 386 #
 387 tryflag CFLAGS_MEMOPS -fno-tree-loop-distribute-patterns
 388
 389 #
 390 # Enable debugging if requessted.
 391 #
 392 test "$debug" = yes && CFLAGS_AUTO=-g
 393
 394 #
 395 # Preprocess asm files to add extra debugging information if debug is
 396 # enabled, our assembler supports the needed directives, and the
 397 # preprocessing script has been written for our architecture.
 398 #
 399 printf "checking whether we should preprocess assembly to add debugging information... "
 400 if fnmatch '-g*|*\ -g*' "$CFLAGS_AUTO $CFLAGS" &&
 401    test -f "tools/add-cfi.$ARCH.awk" &&
 402    printf ".file 1 \"srcfile.s\"\n.line 1\n.cfi_startproc\n.cfi_endproc" | $CC -g -x assembler -c -o /dev/null 2>/dev/null -
 403 then
 404   ADD_CFI=yes
 405 else
 406   ADD_CFI=no
 407 fi
 408 printf "%s\n" "$ADD_CFI"
 409
 410 #
 411 # Possibly add a -O option to CFLAGS and select modules to optimize with
 412 # -O3 based on the status of --enable-optimize and provided CFLAGS.
 413 #
 414 printf "checking for optimization settings... "
 415 case "x$optimize" in
 416 xauto)
 417 if fnmatch '-O*|*\ -O*' "$CFLAGS_AUTO $CFLAGS" ; then
 418 printf "using provided CFLAGS\n" ;optimize=no
 419 else
 420 printf "using defaults\n" ; optimize=yes
 421 fi
 422 ;;
 423 xsize|xnone) printf "minimize size\n" ; optimize=size ;;
 424 xno|x) printf "disabled\n" ; optimize=no ;;
 425 *) printf "custom\n" ;;
 426 esac
 427
 428 test "$optimize" = no || tryflag CFLAGS_AUTO -Os || tryflag CFLAGS_AUTO -O2
 429 test "$optimize" = yes && optimize="internal,malloc,string"
 430
 431 if fnmatch 'no|size' "$optimize" ; then :
 432 else
 433 printf "components to be optimized for speed:"
 434 while test "$optimize" ; do
 435 case "$optimize" in
 436 *,*) this=${optimize%%,*} optimize=${optimize#*,} ;;
 437 *) this=$optimize optimize=
 438 esac
 439 printf " $this"
 440 case "$this" in
 441 */*.c) ;;
 442 */*) this=$this*.c ;;
 443 *) this=$this/*.c ;;
 444 esac
 445 OPTIMIZE_GLOBS="$OPTIMIZE_GLOBS $this"
 446 done
 447 OPTIMIZE_GLOBS=${OPTIMIZE_GLOBS# }
 448 printf "\n"
 449 fi
 450
 451 # Always try -pipe
 452 tryflag CFLAGS_AUTO -pipe
 453
 454 #
 455 # If debugging is disabled, omit frame pointer. Modern GCC does this
 456 # anyway on most archs even when debugging is enabled since the frame
 457 # pointer is no longer needed for debugging.
 458 #
 459 if fnmatch '-g*|*\ -g*' "$CFLAGS_AUTO $CFLAGS" ; then :
 460 else
 461 tryflag CFLAGS_AUTO -fomit-frame-pointer
 462 fi
 463
 464 #
 465 # Modern GCC wants to put DWARF tables (used for debugging and
 466 # unwinding) in the loaded part of the program where they are
 467 # unstrippable. These options force them back to debug sections (and
 468 # cause them not to get generated at all if debugging is off).
 469 #
 470 tryflag CFLAGS_AUTO -fno-unwind-tables
 471 tryflag CFLAGS_AUTO -fno-asynchronous-unwind-tables
 472
 473 #
 474 # Attempt to put each function and each data object in its own
 475 # section. This both allows additional size optimizations at link
 476 # time and works around a dangerous class of compiler/assembler bugs
 477 # whereby relative address expressions are constant-folded by the
 478 # assembler even when one or more of the symbols involved is
 479 # replaceable. See gas pr 18561 and gcc pr 66609, 68178, etc.
 480 #
 481 tryflag CFLAGS_AUTO -ffunction-sections
 482 tryflag CFLAGS_AUTO -fdata-sections
 483
 484 #
 485 # On x86, make sure we don't have incompatible instruction set
 486 # extensions enabled by default. This is bad for making static binaries.
 487 # We cheat and use i486 rather than i386 because i386 really does not
 488 # work anyway (issues with atomic ops).
 489 # Some build environments pass -march and -mtune options via CC, so
 490 # check both CC and CFLAGS.
 491 #
 492 if test "$ARCH" = "i386" ; then
 493 fnmatch '-march=*|*\ -march=*' "$CC $CFLAGS" || tryldflag CFLAGS_AUTO -march=i486
 494 fnmatch '-mtune=*|*\ -mtune=*' "$CC $CFLAGS" || tryldflag CFLAGS_AUTO -mtune=generic
 495 fi
 496
 497 #
 498 # Even with -std=c99, gcc accepts some constructs which are constraint
 499 # violations. We want to treat these as errors regardless of whether
 500 # other purely stylistic warnings are enabled -- especially implicit
 501 # function declarations, which are a dangerous programming error.
 502 #
 503 tryflag CFLAGS_AUTO -Werror=implicit-function-declaration
 504 tryflag CFLAGS_AUTO -Werror=implicit-int
 505 tryflag CFLAGS_AUTO -Werror=pointer-sign
 506 tryflag CFLAGS_AUTO -Werror=pointer-arith
 507
 508 #
 509 # GCC ignores unused arguements by default, but Clang needs this extra
 510 # parameter to stop printing warnings about LDFLAGS passed during
 511 # compiling stage and CFLAGS passed during linking stage.
 512 #
 513 tryflag CFLAGS_AUTO -Qunused-arguments
 514
 515 if test "x$warnings" = xyes ; then
 516 tryflag CFLAGS_AUTO -Wall
 517 tryflag CFLAGS_AUTO -Wno-parentheses
 518 tryflag CFLAGS_AUTO -Wno-uninitialized
 519 tryflag CFLAGS_AUTO -Wno-missing-braces
 520 tryflag CFLAGS_AUTO -Wno-unused-value
 521 tryflag CFLAGS_AUTO -Wno-unused-but-set-variable
 522 tryflag CFLAGS_AUTO -Wno-unknown-pragmas
 523 tryflag CFLAGS_AUTO -Wno-pointer-to-int-cast
 524 fi
 525
 526 if test "x$visibility" = xauto ; then
 527 # This test checks toolchain support for several things:
 528 # - the -include option
 529 # - the attributes/pragmas used in vis.h
 530 # - linking code that takes the address of protected symbols
 531 # - gcc 3.x bug that wrongly claims declarations mismatch
 532 printf "checking whether global visibility preinclude works... "
 533 cat > "$tmpc" <<EOF
 534 __attribute__((__visibility__("default")))
 535 extern struct a *const x;
 536 typedef struct a b;
 537 extern b *const x;
 538 b *const x;
 539 int (*fp)(void);
 540 int foo(void) { }
 541 int bar(void) { fp = foo; return foo(); }
 542 EOF
 543 if $CC $CFLAGS_C99FSE $CPPFLAGS $CFLAGS \
 544   -DSHARED -fPIC -I$srcdir/src/internal -include vis.h \
 545   -nostdlib -shared -Wl,-Bsymbolic-functions \
 546   -o /dev/null "$tmpc" >/dev/null 2>&1 ; then
 547 visibility=yes
 548 else
 549 visibility=no
 550 fi
 551 printf "%s\n" "$visibility"
 552 fi
 553
 554 if test "x$visibility" = xyes ; then
 555 CFLAGS_AUTO="$CFLAGS_AUTO -include vis.h"
 556 CFLAGS_AUTO="${CFLAGS_AUTO# }"
 557 fi
 558
 559 # Determine if the compiler produces position-independent code (PIC)
 560 # by default. If so, we don't need to compile separate object files
 561 # for libc.a and libc.so.
 562 if trycppif __PIC__ "$CFLAGS_C99FSE $CPPFLAGS $CFLAGS" ; then
 563 pic_default=yes
 564 else
 565 pic_default=no
 566 fi
 567
 568 # Reduce space lost to padding for alignment purposes by sorting data
 569 # objects according to their alignment reqirements. This approximates
 570 # optimal packing.
 571 tryldflag LDFLAGS_AUTO -Wl,--sort-section,alignment
 572 tryldflag LDFLAGS_AUTO -Wl,--sort-common
 573
 574 # When linking shared library, drop dummy weak definitions that were
 575 # replaced by strong definitions from other translation units.
 576 tryldflag LDFLAGS_AUTO -Wl,--gc-sections
 577
 578 # Some patched GCC builds have these defaults messed up...
 579 tryldflag LDFLAGS_AUTO -Wl,--hash-style=both
 580
 581 # Prevent linking if there are undefined symbols; if any exist,
 582 # libc.so will crash at runtime during relocation processing.
 583 # The common way this can happen is failure to link the compiler
 584 # runtime library; implementation error is also a possibility.
 585 tryldflag LDFLAGS_AUTO -Wl,--no-undefined
 586
 587 # Avoid exporting symbols from compiler runtime libraries. They
 588 # should be hidden anyway, but some toolchains including old gcc
 589 # versions built without shared library support and pcc are broken.
 590 tryldflag LDFLAGS_AUTO -Wl,--exclude-libs=ALL
 591
 592 # Linking with -Bsymbolic-functions is no longer mandatory for
 593 # the dynamic linker to work, but enable it if it works as
 594 # a linking optimization.
 595 tryldflag LDFLAGS_AUTO -Wl,-Bsymbolic-functions
 596
 597 # Find compiler runtime library
 598 test -z "$LIBCC" && tryldflag LIBCC -lgcc && tryldflag LIBCC -lgcc_eh
 599 test -z "$LIBCC" && tryldflag LIBCC -lcompiler_rt
 600 test -z "$LIBCC" && try_libcc=`$CC -print-file-name=libpcc.a 2>/dev/null` \
 601                  && tryldflag LIBCC "$try_libcc"
 602 printf "using compiler runtime libraries: %s\n" "$LIBCC"
 603
 604 # Figure out arch variants for archs with variants
 605 SUBARCH=
 606 t="$CFLAGS_C99FSE $CPPFLAGS $CFLAGS"
 607
 608 if test "$ARCH" = "x86_64" ; then
 609 trycppif __ILP32__ "$t" && ARCH=x32
 610 fi
 611
 612 if test "$ARCH" = "arm" ; then
 613 if trycppif __thumb2__ "$t" ; then
 614 tryflag CFLAGS_AUTO -Wa,-mimplicit-it=always
 615 tryflag CFLAGS_AUTO -Wa,-mthumb
 616 fi
 617 trycppif __ARMEB__ "$t" && SUBARCH=${SUBARCH}eb
 618 trycppif __ARM_PCS_VFP "$t" && SUBARCH=${SUBARCH}hf
 619 # Versions of clang up until at least 3.8 have the wrong constraint codes
 620 # for floating point operands to inline asm. Detect this so the affected
 621 # source files can just disable the asm.
 622 if test "$cc_family" = clang ; then
 623 printf "checking whether clang's vfp asm constraints work... "
 624 echo 'float f(float x) { __asm__("":"+t"(x)); return x; }' > "$tmpc"
 625 if $CC $CFLAGS_C99FSE $CPPFLAGS $CFLAGS -c -o /dev/null "$tmpc" >/dev/null 2>&1 ; then
 626 printf "yes\n"
 627 else
 628 printf "no\n"
 629 CFLAGS_AUTO="$CFLAGS_AUTO -DBROKEN_VFP_ASM"
 630 CFLAGS_AUTO="${CFLAGS_AUTO# }"
 631 fi
 632 fi
 633 fi
 634
 635 if test "$ARCH" = "aarch64" ; then
 636 trycppif __AARCH64EB__ "$t" && SUBARCH=${SUBARCH}_be
 637 fi
 638
 639 if test "$ARCH" = "mips" ; then
 640 trycppif "__mips_isa_rev >= 6" "$t" && SUBARCH=${SUBARCH}r6
 641 trycppif "_MIPSEL || __MIPSEL || __MIPSEL__" "$t" && SUBARCH=${SUBARCH}el
 642 trycppif __mips_soft_float "$t" && SUBARCH=${SUBARCH}-sf
 643 fi
 644
 645 if test "$ARCH" = "mips64" ; then
 646 trycppif "_MIPS_SIM != _ABI64" "$t" && ARCH=mipsn32
 647 trycppif "__mips_isa_rev >= 6" "$t" && SUBARCH=${SUBARCH}r6
 648 trycppif "_MIPSEL || __MIPSEL || __MIPSEL__" "$t" && SUBARCH=${SUBARCH}el
 649 trycppif __mips_soft_float "$t" && SUBARCH=${SUBARCH}-sf
 650 fi
 651
 652 if test "$ARCH" = "powerpc" ; then
 653 trycppif "__NO_FPRS__ && !_SOFT_FLOAT" "$t" && fail \
 654   "$0: error: compiler's floating point configuration is unsupported"
 655 trycppif _SOFT_FLOAT "$t" && SUBARCH=${SUBARCH}-sf
 656 fi
 657
 658 test "$ARCH" = "microblaze" && trycppif __MICROBLAZEEL__ "$t" \
 659 && SUBARCH=${SUBARCH}el
 660
 661 if test "$ARCH" = "powerpc64" ; then
 662 trycppif "_CALL_ELF == 2" "$t" || fail "$0: error: unsupported powerpc64 ABI"
 663 trycppif __LITTLE_ENDIAN__ "$t" && SUBARCH=${SUBARCH}le
 664 trycppif _SOFT_FLOAT "$t" && fail "$0: error: soft-float not supported on powerpc64"
 665 fi
 666
 667 if test "$ARCH" = "sh" ; then
 668 tryflag CFLAGS_AUTO -Wa,--isa=any
 669 trycppif __BIG_ENDIAN__ "$t" && SUBARCH=${SUBARCH}eb
 670 if trycppif "__SH_FPU_ANY__ || __SH4__" "$t" ; then
 671 # Some sh configurations are broken and replace double with float
 672 # rather than using softfloat when the fpu is present but only
 673 # supports single precision. Reject them.
 674 printf "checking whether compiler's double type is IEEE double... "
 675 echo 'typedef char dblcheck[(int)sizeof(double)-5];' > "$tmpc"
 676 if $CC $CFLAGS_C99FSE $CPPFLAGS $CFLAGS -c -o /dev/null "$tmpc" >/dev/null 2>&1 ; then
 677 printf "yes\n"
 678 else
 679 printf "no\n"
 680 fail "$0: error: compiler's floating point configuration is unsupported"
 681 fi
 682 else
 683 SUBARCH=${SUBARCH}-nofpu
 684 fi
 685 if trycppif __SH_FDPIC__ "$t" ; then
 686 SUBARCH=${SUBARCH}-fdpic
 687 fi
 688 fi
 689
 690 test "$SUBARCH" \
 691 && printf "configured for %s variant: %s\n" "$ARCH" "$ARCH$SUBARCH"
 692
 693 case "$ARCH$SUBARCH" in
 694 arm) ASMSUBARCH=el ;;
 695 *) ASMSUBARCH=$SUBARCH ;;
 696 esac
 697
 698 #
 699 # Some archs (powerpc) have different possible long double formats
 700 # that the compiler can be configured for. The logic for whether this
 701 # is supported is in bits/float.h; in general, it is not. We need to
 702 # check for mismatches here or code in printf, strotd, and scanf will
 703 # be dangerously incorrect because it depends on (1) the macros being
 704 # correct, and (2) IEEE semantics.
 705 #
 706 printf "checking whether compiler's long double definition matches float.h... "
 707 echo '#include <float.h>' > "$tmpc"
 708 echo '#if LDBL_MANT_DIG == 53' >> "$tmpc"
 709 echo 'typedef char ldcheck[9-(int)sizeof(long double)];' >> "$tmpc"
 710 echo '#endif' >> "$tmpc"
 711 if $CC $CFLAGS_C99FSE \
 712   -I$srcdir/arch/$ARCH -I$srcdir/arch/generic -I$srcdir/include \
 713   $CPPFLAGS $CFLAGS -c -o /dev/null "$tmpc" >/dev/null 2>&1 ; then
 714 printf "yes\n"
 715 else
 716 printf "no\n"
 717 fail "$0: error: unsupported long double type"
 718 fi
 719
 720 #
 721 # Some build systems globally pass in broken CFLAGS like -ffast-math
 722 # for all packages. On recent GCC we can detect this and error out
 723 # early rather than producing a seriously-broken math library.
 724 #
 725 if trycppif "__FAST_MATH__" \
 726   "$CFLAGS_C99FSE $CPPFLAGS $CFLAGS" ; then
 727 fail "$0: error: compiler has broken floating point; check CFLAGS"
 728 fi
 729
 730 printf "creating config.mak... "
 731
 732 cmdline=$(quote "$0")
 733 for i ; do cmdline="$cmdline $(quote "$i")" ; done
 734
 735 exec 3>&1 1>config.mak
 736
 737
 738 cat << EOF
 739 # This version of config.mak was generated by:
 740 # $cmdline
 741 # Any changes made here will be lost if configure is re-run
 742 ARCH = $ARCH
 743 SUBARCH = $SUBARCH
 744 ASMSUBARCH = $ASMSUBARCH
 745 srcdir = $srcdir
 746 prefix = $prefix
 747 exec_prefix = $exec_prefix
 748 bindir = $bindir
 749 libdir = $libdir
 750 includedir = $includedir
 751 syslibdir = $syslibdir
 752 CC = $CC
 753 CFLAGS = $CFLAGS
 754 CFLAGS_AUTO = $CFLAGS_AUTO
 755 CFLAGS_C99FSE = $CFLAGS_C99FSE
 756 CFLAGS_MEMOPS = $CFLAGS_MEMOPS
 757 CFLAGS_NOSSP = $CFLAGS_NOSSP
 758 CPPFLAGS = $CPPFLAGS
 759 LDFLAGS = $LDFLAGS
 760 LDFLAGS_AUTO = $LDFLAGS_AUTO
 761 CROSS_COMPILE = $CROSS_COMPILE
 762 LIBCC = $LIBCC
 763 OPTIMIZE_GLOBS = $OPTIMIZE_GLOBS
 764 ALL_TOOLS = $tools
 765 TOOL_LIBS = $tool_libs
 766 ADD_CFI = $ADD_CFI
 767 EOF
 768 test "x$static" = xno && echo "STATIC_LIBS ="
 769 test "x$shared" = xno && echo "SHARED_LIBS ="
 770 test "x$cc_family" = xgcc && echo 'WRAPCC_GCC = $(CC)'
 771 test "x$cc_family" = xclang && echo 'WRAPCC_CLANG = $(CC)'
 772 test "x$pic_default" = xyes && echo 'AOBJS = $(LOBJS)'
 773 exec 1>&3 3>&-
 774
 775 test "$srcdir" = "." || ln -sf $srcdir/Makefile .
 776
 777 printf "done\n"