allow specifying argv[0] when invoking a program via ldso command
[musl.git] / configure
blob539c9fcbe6271919fbddc112d5b9fe42dfb89390
1 #!/bin/sh
3 usage () {
4 cat <<EOF
5 Usage: $0 [OPTION]... [VAR=VALUE]... [TARGET]
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.
10 Defaults for the options are specified in brackets.
12 Configuration:
13 --srcdir=DIR source directory [detected]
15 Installation directories:
16 --prefix=PREFIX main installation prefix [/usr/local/musl]
17 --exec-prefix=EPREFIX installation prefix for executable files [PREFIX]
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]
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
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]
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]
45 Use these variables to override the choices made by configure.
47 EOF
48 exit 0
51 # Helper functions
53 quote () {
54 tr '\n' ' ' <<EOF | grep '^[-[:alnum:]_=,./:]* $' >/dev/null 2>&1 && { echo "$1" ; return 0 ; }
56 EOF
57 printf %s\\n "$1" | sed -e "s/'/'\\\\''/g" -e "1s/^/'/" -e "\$s/\$/'/" -e "s#^'\([-[:alnum:]_,./:]*\)=\(.*\)\$#\1='\2#"
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 ; }
65 stripdir () {
66 while eval "fnmatch '*/' \"\${$1}\"" ; do eval "$1=\${$1%/}" ; done
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
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
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=\${$1# }"
105 return 0
106 else
107 printf "no\n"
108 return 1
114 # Beginning of actual script
116 CFLAGS_C99FSE=
117 CFLAGS_AUTO=
118 CFLAGS_MEMOPS=
119 CFLAGS_NOSSP=
120 CFLAGS_TRY=
121 LDFLAGS_AUTO=
122 LDFLAGS_TRY=
123 OPTIMIZE_GLOBS=
124 srcdir=
125 prefix=/usr/local/musl
126 exec_prefix='$(prefix)'
127 bindir='$(exec_prefix)/bin'
128 libdir='$(prefix)/lib'
129 includedir='$(prefix)/include'
130 syslibdir='/lib'
131 tools=
132 tool_libs=
133 build=
134 target=
135 optimize=auto
136 debug=no
137 warnings=no
138 visibility=auto
139 shared=auto
140 static=yes
141 wrapper=auto
142 gcc_wrapper=no
143 clang_wrapper=no
145 for arg ; do
146 case "$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
190 for i in srcdir prefix exec_prefix bindir libdir includedir syslibdir ; do
191 stripdir $i
192 done
195 # Get the source dir for out-of-tree builds
197 if test -z "$srcdir" ; then
198 srcdir="${0%/configure}"
199 stripdir srcdir
201 abs_builddir="$(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 "$0: Makefile already exists in the working directory"
207 # Get a temp filename we can use
210 set -C
211 while : ; do i=$(($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
220 # Check whether we are cross-compiling, and set a default
221 # CROSS_COMPILE prefix if none was provided.
223 test "$target" && \
224 test "$target" != "$build" && \
225 test -z "$CROSS_COMPILE" && \
226 CROSS_COMPILE="$target-"
229 # Find a C compiler to use
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 "$0: cannot find a C compiler" ; exit 1 ; }
238 printf "checking whether C compiler works... "
239 echo "typedef int x;" > "$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" "$output"
244 exit 1
248 # Figure out options to force errors on unknown flags.
250 tryflag CFLAGS_TRY -Werror=unknown-warning-option
251 tryflag CFLAGS_TRY -Werror=unused-command-line-argument
252 tryflag CFLAGS_TRY -Werror=ignored-optimization-argument
253 tryldflag LDFLAGS_TRY -Werror=unknown-warning-option
254 tryldflag LDFLAGS_TRY -Werror=unused-command-line-argument
257 # Need to know if the compiler is gcc or clang to decide which toolchain
258 # wrappers to build.
260 printf "checking for C compiler family... "
261 cc_ver="$(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*' "$cc_ver" ; then
266 cc_family=clang
268 echo "$cc_family"
271 # Figure out toolchain wrapper to build
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 "$0: could not find an appropriate toolchain wrapper"
295 if test "$gcc_wrapper" = yes ; then
296 tools="$tools obj/musl-gcc"
297 tool_libs="$tool_libs lib/musl-gcc.specs"
299 if test "$clang_wrapper" = yes ; then
300 tools="$tools obj/musl-clang obj/ld.musl-clang"
304 # Find the target architecture
306 printf "checking target system type... "
307 test -n "$target" || target=$($CC -dumpmachine 2>/dev/null) || target=unknown
308 printf "%s\n" "$target"
311 # Convert to just ARCH
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
335 # Try to get a conforming C99 freestanding environment
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 "$ARCH" = i386 && tryflag CFLAGS_C99FSE -ffloat-store ; }
343 tryflag CFLAGS_C99FSE -frounding-math
346 # We may use the may_alias attribute if __GNUC__ is defined, so
347 # if the compiler defines __GNUC__ but does not provide it,
348 # it must be defined away as part of the CFLAGS.
350 printf "checking whether compiler needs attribute((may_alias)) suppression... "
351 cat > "$tmpc" <<EOF
352 typedef int
353 #ifdef __GNUC__
354 __attribute__((__may_alias__))
355 #endif
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="$CFLAGS_C99FSE -D__may_alias__="
367 # The GNU toolchain defaults to assuming unmarked files need an
368 # executable stack, potentially exposing vulnerabilities in programs
369 # linked with such object files. Fix this.
371 tryflag CFLAGS_C99FSE -Wa,--noexecstack
374 # Check for options to disable stack protector, which needs to be
375 # disabled for a few early-bootstrap translation units. If not found,
376 # this is not an error; we assume the toolchain does not do ssp.
378 tryflag CFLAGS_NOSSP -fno-stack-protector
381 # Check for options that may be needed to prevent the compiler from
382 # generating self-referential versions of memcpy,, memmove, memcmp,
383 # and memset. Really, we should add a check to determine if this
384 # option is sufficient, and if not, add a macro to cripple these
385 # functions with volatile...
387 tryflag CFLAGS_MEMOPS -fno-tree-loop-distribute-patterns
390 # Enable debugging if requessted.
392 test "$debug" = yes && CFLAGS_AUTO=-g
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.
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" | $CC -g -x assembler -c -o /dev/null 2>/dev/null -
403 then
404 ADD_CFI=yes
405 else
406 ADD_CFI=no
408 printf "%s\n" "$ADD_CFI"
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.
414 printf "checking for optimization settings... "
415 case "x$optimize" in
416 xauto)
417 if fnmatch '-O*|*\ -O*' "$CFLAGS_AUTO $CFLAGS" ; then
418 printf "using provided CFLAGS\n" ;optimize=no
419 else
420 printf "using defaults\n" ; optimize=yes
423 xsize|xnone) printf "minimize size\n" ; optimize=size ;;
424 xno|x) printf "disabled\n" ; optimize=no ;;
425 *) printf "custom\n" ;;
426 esac
428 test "$optimize" = no || tryflag CFLAGS_AUTO -Os || tryflag CFLAGS_AUTO -O2
429 test "$optimize" = yes && optimize="internal,malloc,string"
431 if fnmatch 'no|size' "$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"
451 # Always try -pipe
452 tryflag CFLAGS_AUTO -pipe
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.
459 if fnmatch '-g*|*\ -g*' "$CFLAGS_AUTO $CFLAGS" ; then :
460 else
461 tryflag CFLAGS_AUTO -fomit-frame-pointer
465 # Modern GCC wants to put DWARF tables (used for debugging and
466 # unwinding) in the loaded part of the program where they are
467 # unstrippable. These options force them back to debug sections (and
468 # cause them not to get generated at all if debugging is off).
470 tryflag CFLAGS_AUTO -fno-unwind-tables
471 tryflag CFLAGS_AUTO -fno-asynchronous-unwind-tables
474 # Attempt to put each function and each data object in its own
475 # section. This both allows additional size optimizations at link
476 # time and works around a dangerous class of compiler/assembler bugs
477 # whereby relative address expressions are constant-folded by the
478 # assembler even when one or more of the symbols involved is
479 # replaceable. See gas pr 18561 and gcc pr 66609, 68178, etc.
481 tryflag CFLAGS_AUTO -ffunction-sections
482 tryflag CFLAGS_AUTO -fdata-sections
485 # On x86, make sure we don't have incompatible instruction set
486 # extensions enabled by default. This is bad for making static binaries.
487 # We cheat and use i486 rather than i386 because i386 really does not
488 # work anyway (issues with atomic ops).
489 # Some build environments pass -march and -mtune options via CC, so
490 # check both CC and CFLAGS.
492 if test "$ARCH" = "i386" ; then
493 fnmatch '-march=*|*\ -march=*' "$CC $CFLAGS" || tryldflag CFLAGS_AUTO -march=i486
494 fnmatch '-mtune=*|*\ -mtune=*' "$CC $CFLAGS" || tryldflag CFLAGS_AUTO -mtune=generic
498 # Even with -std=c99, gcc accepts some constructs which are constraint
499 # violations. We want to treat these as errors regardless of whether
500 # other purely stylistic warnings are enabled -- especially implicit
501 # function declarations, which are a dangerous programming error.
503 tryflag CFLAGS_AUTO -Werror=implicit-function-declaration
504 tryflag CFLAGS_AUTO -Werror=implicit-int
505 tryflag CFLAGS_AUTO -Werror=pointer-sign
506 tryflag CFLAGS_AUTO -Werror=pointer-arith
509 # GCC ignores unused arguements by default, but Clang needs this extra
510 # parameter to stop printing warnings about LDFLAGS passed during
511 # compiling stage and CFLAGS passed during linking stage.
513 tryflag CFLAGS_AUTO -Qunused-arguments
515 if test "x$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
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(); }
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 "$tmpc" >/dev/null 2>&1 ; then
547 visibility=yes
548 else
549 visibility=no
551 printf "%s\n" "$visibility"
554 if test "x$visibility" = xyes ; then
555 CFLAGS_AUTO="$CFLAGS_AUTO -include vis.h"
556 CFLAGS_AUTO="${CFLAGS_AUTO# }"
559 # Determine if the compiler produces position-independent code (PIC)
560 # by default. If so, we don't need to compile separate object files
561 # for libc.a and libc.so.
562 if trycppif __PIC__ "$CFLAGS_C99FSE $CPPFLAGS $CFLAGS" ; then
563 pic_default=yes
564 else
565 pic_default=no
568 # Reduce space lost to padding for alignment purposes by sorting data
569 # objects according to their alignment reqirements. This approximates
570 # optimal packing.
571 tryldflag LDFLAGS_AUTO -Wl,--sort-section,alignment
572 tryldflag LDFLAGS_AUTO -Wl,--sort-common
574 # When linking shared library, drop dummy weak definitions that were
575 # replaced by strong definitions from other translation units.
576 tryldflag LDFLAGS_AUTO -Wl,--gc-sections
578 # Some patched GCC builds have these defaults messed up...
579 tryldflag LDFLAGS_AUTO -Wl,--hash-style=both
581 # Prevent linking if there are undefined symbols; if any exist,
582 # libc.so will crash at runtime during relocation processing.
583 # The common way this can happen is failure to link the compiler
584 # runtime library; implementation error is also a possibility.
585 tryldflag LDFLAGS_AUTO -Wl,--no-undefined
587 # Avoid exporting symbols from compiler runtime libraries. They
588 # should be hidden anyway, but some toolchains including old gcc
589 # versions built without shared library support and pcc are broken.
590 tryldflag LDFLAGS_AUTO -Wl,--exclude-libs=ALL
592 # Linking with -Bsymbolic-functions is no longer mandatory for
593 # the dynamic linker to work, but enable it if it works as
594 # a linking optimization.
595 tryldflag LDFLAGS_AUTO -Wl,-Bsymbolic-functions
597 # Find compiler runtime library
598 test -z "$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" "$LIBCC"
604 # Figure out arch variants for archs with variants
605 SUBARCH=
606 t="$CFLAGS_C99FSE $CPPFLAGS $CFLAGS"
608 if test "$ARCH" = "x86_64" ; then
609 trycppif __ILP32__ "$t" && ARCH=x32
612 if test "$ARCH" = "arm" ; then
613 if trycppif __thumb2__ "$t" ; then
614 tryflag CFLAGS_AUTO -Wa,-mimplicit-it=always
615 tryflag CFLAGS_AUTO -Wa,-mthumb
617 trycppif __ARMEB__ "$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# }"
635 if test "$ARCH" = "aarch64" ; then
636 trycppif __AARCH64EB__ "$t" && SUBARCH=${SUBARCH}_be
639 if test "$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
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
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=${SUBARCH}-sf
658 test "$ARCH" = "microblaze" && trycppif __MICROBLAZEEL__ "$t" \
659 && SUBARCH=${SUBARCH}el
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 "$0: error: soft-float not supported on powerpc64"
667 if test "$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 "$0: error: compiler's floating point configuration is unsupported"
682 else
683 SUBARCH=${SUBARCH}-nofpu
685 if trycppif __SH_FDPIC__ "$t" ; then
686 SUBARCH=${SUBARCH}-fdpic
690 test "$SUBARCH" \
691 && printf "configured for %s variant: %s\n" "$ARCH" "$ARCH$SUBARCH"
693 case "$ARCH$SUBARCH" in
694 arm) ASMSUBARCH=el ;;
695 *) ASMSUBARCH=$SUBARCH ;;
696 esac
699 # Some archs (powerpc) have different possible long double formats
700 # that the compiler can be configured for. The logic for whether this
701 # is supported is in bits/float.h; in general, it is not. We need to
702 # check for mismatches here or code in printf, strotd, and scanf will
703 # be dangerously incorrect because it depends on (1) the macros being
704 # correct, and (2) IEEE semantics.
706 printf "checking whether compiler's long double definition matches float.h... "
707 echo '#include <float.h>' > "$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 "$0: error: unsupported long double type"
721 # Some build systems globally pass in broken CFLAGS like -ffast-math
722 # for all packages. On recent GCC we can detect this and error out
723 # early rather than producing a seriously-broken math library.
725 if trycppif "__FAST_MATH__" \
726 "$CFLAGS_C99FSE $CPPFLAGS $CFLAGS" ; then
727 fail "$0: error: compiler has broken floating point; check CFLAGS"
730 printf "creating config.mak... "
732 cmdline=$(quote "$0")
733 for i ; do cmdline="$cmdline $(quote "$i")" ; done
735 exec 3>&1 1>config.mak
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 = $ADD_CFI
768 test "x$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 = $(LOBJS)'
773 exec 1>&3 3>&-
775 test "$srcdir" = "." || ln -sf $srcdir/Makefile .
777 printf "done\n"