about summary refs log tree commit diff
path: root/configure
blob: 18fda9afc55932b55ac7a3a566c13cf0c1c3cf83 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
#!/bin/sh

usage () {
cat <<EOF
Usage: $0 [OPTION]... [VAR=VALUE]... [TARGET]

To assign environment variables (e.g., CC, CFLAGS...), specify them as
VAR=VALUE.  See below for descriptions of some of the useful variables.

Defaults for the options are specified in brackets.

Configuration:
  --srcdir=DIR            source directory [detected]

Installation directories:
  --prefix=PREFIX         main installation prefix [/usr/local/musl]
  --exec-prefix=EPREFIX   installation prefix for executable files [PREFIX]

Fine tuning of the installation directories:
  --bindir=DIR            user executables [EPREFIX/bin]
  --libdir=DIR            library files for the linker [PREFIX/lib]
  --includedir=DIR        include files for the C compiler [PREFIX/include]
  --syslibdir=DIR         location for the dynamic linker [/lib]

System types:
  --target=TARGET         configure to run on target TARGET [detected]
  --host=HOST             same as --target
  --build=BUILD           build system type; used only to infer cross-compiling

Optional features:
  --enable-optimize=...   optimize listed components for speed over size [auto]
  --enable-debug          build with debugging information [disabled]
  --enable-warnings       build with recommended warnings flags [disabled]
  --enable-wrapper=...    build given musl toolchain wrapper [auto]
  --disable-shared        inhibit building shared library [enabled]
  --disable-static        inhibit building static library [enabled]

Optional packages:
  --with-malloc=...       choose malloc implementation [mallocng]

Some influential environment variables:
  CC                      C compiler command [detected]
  CFLAGS                  C compiler flags [-Os -pipe ...]
  CROSS_COMPILE           prefix for cross compiler and tools [none]
  LIBCC                   compiler runtime library [detected]

Use these variables to override the choices made by configure.

EOF
exit 0
}

# Helper functions

quote () {
tr '\n' ' ' <<EOF | grep '^[-[:alnum:]_=,./:]* $' >/dev/null 2>&1 && { echo "$1" ; return 0 ; }
$1
EOF
printf %s\\n "$1" | sed -e "s/'/'\\\\''/g" -e "1s/^/'/" -e "\$s/\$/'/" -e "s#^'\([-[:alnum:]_,./:]*\)=\(.*\)\$#\1='\2#"
}
echo () { printf "%s\n" "$*" ; }
fail () { echo "$*" ; exit 1 ; }
fnmatch () { eval "case \"\$2\" in $1) return 0 ;; *) return 1 ;; esac" ; }
cmdexists () { type "$1" >/dev/null 2>&1 ; }
trycc () { test -z "$CC" && cmdexists "$1" && CC=$1 ; }

stripdir () {
while eval "fnmatch '*/' \"\${$1}\"" ; do eval "$1=\${$1%/}" ; done
}

trycppif () {
printf "checking preprocessor condition %s... " "$1"
echo "typedef int x;" > "$tmpc"
echo "#if $1" >> "$tmpc"
echo "#error yes" >> "$tmpc"
echo "#endif" >> "$tmpc"
if $CC $2 -c -o /dev/null "$tmpc" >/dev/null 2>&1 ; then
printf "false\n"
return 1
else
printf "true\n"
return 0
fi
}

tryflag () {
printf "checking whether compiler accepts %s... " "$2"
echo "typedef int x;" > "$tmpc"
if $CC $CFLAGS_TRY $2 -c -o /dev/null "$tmpc" >/dev/null 2>&1 ; then
printf "yes\n"
eval "$1=\"\${$1} \$2\""
eval "$1=\${$1# }"
return 0
else
printf "no\n"
return 1
fi
}

tryldflag () {
printf "checking whether linker accepts %s... " "$2"
echo "typedef int x;" > "$tmpc"
if $CC $LDFLAGS_TRY -nostdlib -shared "$2" -o /dev/null "$tmpc" >/dev/null 2>&1 ; then
printf "yes\n"
eval "$1=\"\${$1} \$2\""
eval "$1=\${$1# }"
return 0
else
printf "no\n"
return 1
fi
}



# Beginning of actual script

CFLAGS_C99FSE=
CFLAGS_AUTO=
CFLAGS_MEMOPS=
CFLAGS_NOSSP=
CFLAGS_TRY=
LDFLAGS_AUTO=
LDFLAGS_TRY=
OPTIMIZE_GLOBS=
srcdir=
prefix=/usr/local/musl
exec_prefix='$(prefix)'
bindir='$(exec_prefix)/bin'
libdir='$(prefix)/lib'
includedir='$(prefix)/include'
syslibdir='/lib'
tools=
tool_libs=
build=
target=
optimize=auto
debug=no
warnings=no
shared=auto
static=yes
wrapper=auto
gcc_wrapper=no
clang_wrapper=no
malloc_dir=mallocng

for arg ; do
case "$arg" in
--help|-h) usage ;;
--srcdir=*) srcdir=${arg#*=} ;;
--prefix=*) prefix=${arg#*=} ;;
--exec-prefix=*) exec_prefix=${arg#*=} ;;
--bindir=*) bindir=${arg#*=} ;;
--libdir=*) libdir=${arg#*=} ;;
--includedir=*) includedir=${arg#*=} ;;
--syslibdir=*) syslibdir=${arg#*=} ;;
--enable-shared|--enable-shared=yes) shared=yes ;;
--disable-shared|--enable-shared=no) shared=no ;;
--enable-static|--enable-static=yes) static=yes ;;
--disable-static|--enable-static=no) static=no ;;
--enable-optimize) optimize=yes ;;
--enable-optimize=*) optimize=${arg#*=} ;;
--disable-optimize) optimize=no ;;
--enable-debug|--enable-debug=yes) debug=yes ;;
--disable-debug|--enable-debug=no) debug=no ;;
--enable-warnings|--enable-warnings=yes) warnings=yes ;;
--disable-warnings|--enable-warnings=no) warnings=no ;;
--enable-wrapper|--enable-wrapper=yes) wrapper=detect ;;
--enable-wrapper=all) wrapper=yes ; gcc_wrapper=yes ; clang_wrapper=yes ;;
--enable-wrapper=gcc) wrapper=yes ; gcc_wrapper=yes ;;
--enable-wrapper=clang) wrapper=yes ; clang_wrapper=yes ;;
--disable-wrapper|--enable-wrapper=no) wrapper=no ;;
--enable-gcc-wrapper|--enable-gcc-wrapper=yes) wrapper=yes ; gcc_wrapper=yes ;;
--disable-gcc-wrapper|--enable-gcc-wrapper=no) wrapper=no ;;
--with-malloc=*) malloc_dir=${arg#*=} ;;
--enable-*|--disable-*|--with-*|--without-*|--*dir=*) ;;
--host=*|--target=*) target=${arg#*=} ;;
--build=*) build=${arg#*=} ;;
-* ) echo "$0: unknown option $arg" ;;
AR=*) AR=${arg#*=} ;;
RANLIB=*) RANLIB=${arg#*=} ;;
CC=*) CC=${arg#*=} ;;
CFLAGS=*) CFLAGS=${arg#*=} ;;
CPPFLAGS=*) CPPFLAGS=${arg#*=} ;;
LDFLAGS=*) LDFLAGS=${arg#*=} ;;
CROSS_COMPILE=*) CROSS_COMPILE=${arg#*=} ;;
LIBCC=*) LIBCC=${arg#*=} ;;
*=*) ;;
*) build=$arg ; target=$arg ;;
esac
done

for i in srcdir prefix exec_prefix bindir libdir includedir syslibdir ; do
stripdir $i
done

#
# Get the source dir for out-of-tree builds
#
if test -z "$srcdir" ; then
srcdir="${0%/configure}"
stripdir srcdir
fi
abs_builddir="$(pwd)" || fail "$0: cannot determine working directory"
abs_srcdir="$(cd $srcdir && pwd)" || fail "$0: invalid source directory $srcdir"
test "$abs_srcdir" = "$abs_builddir" && srcdir=.
test "$srcdir" != "." -a -f Makefile -a ! -h Makefile && fail "$0: Makefile already exists in the working directory"

#
# Get a temp filename we can use
#
i=0
set -C
while : ; do i=$(($i+1))
tmpc="./conf$$-$PPID-$i.c"
2>|/dev/null > "$tmpc" && break
test "$i" -gt 50 && fail "$0: cannot create temporary file $tmpc"
done
set +C
trap 'rm "$tmpc"' EXIT INT QUIT TERM HUP

#
# Check that the requested malloc implementation exists
#
test -d "$srcdir/src/malloc/$malloc_dir" \
|| fail "$0: error: chosen malloc implementation '$malloc_dir' does not exist"

#
# Check whether we are cross-compiling, and set a default
# CROSS_COMPILE prefix if none was provided.
#
test "$target" && \
test "$target" != "$build" && \
test -z "$CROSS_COMPILE" && \
CROSS_COMPILE="$target-"

#
# Find a C compiler to use
#
printf "checking for C compiler... "
trycc ${CROSS_COMPILE}gcc
trycc ${CROSS_COMPILE}c99
trycc ${CROSS_COMPILE}cc
printf "%s\n" "$CC"
test -n "$CC" || { echo "$0: cannot find a C compiler" ; exit 1 ; }

printf "checking whether C compiler works... "
echo "typedef int x;" > "$tmpc"
if output=$($CC $CPPFLAGS $CFLAGS -c -o /dev/null "$tmpc" 2>&1) ; then
printf "yes\n"
else
printf "no; compiler output follows:\n%s\n" "$output"
exit 1
fi

#
# Figure out options to force errors on unknown flags.
#
tryflag   CFLAGS_TRY  -Werror=unknown-warning-option
tryflag   CFLAGS_TRY  -Werror=unused-command-line-argument
tryflag   CFLAGS_TRY  -Werror=ignored-optimization-argument
tryldflag LDFLAGS_TRY -Werror=unknown-warning-option
tryldflag LDFLAGS_TRY -Werror=unused-command-line-argument

#
# Need to know if the compiler is gcc or clang to decide which toolchain
# wrappers to build.
#
printf "checking for C compiler family... "
cc_ver="$(LC_ALL=C $CC -v 2>&1)"
cc_family=unknown
if fnmatch '*gcc\ version*' "$cc_ver" ; then
cc_family=gcc
elif fnmatch '*clang\ version*' "$cc_ver" ; then
cc_family=clang
fi
echo "$cc_family"

#
# Figure out toolchain wrapper to build
#
if test "$wrapper" = auto -o "$wrapper" = detect ; then
echo "#include <stdlib.h>" > "$tmpc"
echo "#if ! __GLIBC__" >> "$tmpc"
echo "#error no" >> "$tmpc"
echo "#endif" >> "$tmpc"
printf "checking for toolchain wrapper to build... "
if test "$wrapper" = auto && ! $CC -c -o /dev/null "$tmpc" >/dev/null 2>&1 ; then
echo "none"
elif test "$cc_family" = gcc ; then
gcc_wrapper=yes
echo "gcc"
elif test "$cc_family" = clang ; then
clang_wrapper=yes
echo "clang"
else
echo "none"
if test "$wrapper" = detect ; then
fail "$0: could not find an appropriate toolchain wrapper"
fi
fi
fi

if test "$gcc_wrapper" = yes ; then
tools="$tools obj/musl-gcc"
tool_libs="$tool_libs lib/musl-gcc.specs"
fi
if test "$clang_wrapper" = yes ; then
tools="$tools obj/musl-clang obj/ld.musl-clang"
fi

#
# Find the target architecture
#
printf "checking target system type... "
test -n "$target" || target=$($CC -dumpmachine 2>/dev/null) || target=unknown
printf "%s\n" "$target"

#
# Convert to just ARCH
#
case "$target" in
# Catch these early to simplify matching for 32-bit archs
arm*) ARCH=arm ;;
aarch64*) ARCH=aarch64 ;;
i?86-nt32*) ARCH=nt32 ;;
i?86*) ARCH=i386 ;;
x86_64-x32*|x32*|x86_64*x32) ARCH=x32 ;;
x86_64-nt64*) ARCH=nt64 ;;
x86_64*) ARCH=x86_64 ;;
m68k*) ARCH=m68k ;;
mips64*|mipsisa64*) ARCH=mips64 ;;
mips*) ARCH=mips ;;
microblaze*) ARCH=microblaze ;;
or1k*) ARCH=or1k ;;
powerpc64*|ppc64*) ARCH=powerpc64 ;;
powerpc*|ppc*) ARCH=powerpc ;;
riscv64*) ARCH=riscv64 ;;
sh[1-9bel-]*|sh|superh*) ARCH=sh ;;
s390x*) ARCH=s390x ;;
unknown) fail "$0: unable to detect target arch; try $0 --target=..." ;;
*) fail "$0: unknown or unsupported target \"$target\"" ;;
esac

#
# Try to get a conforming C99 freestanding environment
#
tryflag CFLAGS_C99FSE -std=c99
tryflag CFLAGS_C99FSE -nostdinc
tryflag CFLAGS_C99FSE -ffreestanding \
|| tryflag CFLAGS_C99FSE -fno-builtin
tryflag CFLAGS_C99FSE -fexcess-precision=standard \
|| { test "$ARCH" = i386 && tryflag CFLAGS_C99FSE -ffloat-store ; }
tryflag CFLAGS_C99FSE -frounding-math

#
# We may use the may_alias attribute if __GNUC__ is defined, so
# if the compiler defines __GNUC__ but does not provide it,
# it must be defined away as part of the CFLAGS.
#
printf "checking whether compiler needs attribute((may_alias)) suppression... "
cat > "$tmpc" <<EOF
typedef int
#ifdef __GNUC__
__attribute__((__may_alias__))
#endif
x;
EOF
if $CC $CFLAGS_C99FSE $CPPFLAGS $CFLAGS \
  -c -o /dev/null "$tmpc" >/dev/null 2>&1 ; then
printf "no\n"
else
printf "yes\n"
CFLAGS_C99FSE="$CFLAGS_C99FSE -D__may_alias__="
fi

#
# The GNU toolchain defaults to assuming unmarked files need an
# executable stack, potentially exposing vulnerabilities in programs
# linked with such object files. Fix this.
#
tryflag CFLAGS_C99FSE -Wa,--noexecstack

#
# Check for options to disable stack protector, which needs to be
# disabled for a few early-bootstrap translation units. If not found,
# this is not an error; we assume the toolchain does not do ssp.
#
tryflag CFLAGS_NOSSP -fno-stack-protector

#
# Check for options that may be needed to prevent the compiler from
# generating self-referential versions of memcpy,, memmove, memcmp,
# and memset. Really, we should add a check to determine if this
# option is sufficient, and if not, add a macro to cripple these
# functions with volatile...
#
tryflag CFLAGS_MEMOPS -fno-tree-loop-distribute-patterns

#
# Enable debugging if requessted.
#
test "$debug" = yes && CFLAGS_AUTO=-g

#
# Preprocess asm files to add extra debugging information if debug is
# enabled, our assembler supports the needed directives, and the
# preprocessing script has been written for our architecture.
#
printf "checking whether we should preprocess assembly to add debugging information... "
if fnmatch '-g*|*\ -g*' "$CFLAGS_AUTO $CFLAGS" &&
   test -f "tools/add-cfi.$ARCH.awk" &&
   printf ".file 1 \"srcfile.s\"\n.line 1\n.cfi_startproc\n.cfi_endproc" | $CC -g -x assembler -c -o /dev/null 2>/dev/null -
then
  ADD_CFI=yes
else
  ADD_CFI=no
fi
printf "%s\n" "$ADD_CFI"

#
# Possibly add a -O option to CFLAGS and select modules to optimize with
# -O3 based on the status of --enable-optimize and provided CFLAGS.
#
printf "checking for optimization settings... "
case "x$optimize" in
xauto)
if fnmatch '-O*|*\ -O*' "$CFLAGS_AUTO $CFLAGS" ; then
printf "using provided CFLAGS\n" ;optimize=no
else
printf "using defaults\n" ; optimize=yes
fi
;;
xsize|xnone) printf "minimize size\n" ; optimize=size ;;
xno|x) printf "disabled\n" ; optimize=no ;;
*) printf "custom\n" ;;
esac

test "$optimize" = no || tryflag CFLAGS_AUTO -Os || tryflag CFLAGS_AUTO -O2
test "$optimize" = yes && optimize="internal,malloc,string"

if fnmatch 'no|size' "$optimize" ; then :
else
printf "components to be optimized for speed:"
while test "$optimize" ; do
case "$optimize" in
*,*) this=${optimize%%,*} optimize=${optimize#*,} ;;
*) this=$optimize optimize=
esac
printf " $this"
case "$this" in
*/*.c) ;;
*/*) this=$this*.c ;;
*) this=$this/*.c ;;
esac
OPTIMIZE_GLOBS="$OPTIMIZE_GLOBS $this"
done
OPTIMIZE_GLOBS=${OPTIMIZE_GLOBS# }
printf "\n"
fi

# Always try -pipe
tryflag CFLAGS_AUTO -pipe

#
# If debugging is disabled, omit frame pointer. Modern GCC does this
# anyway on most archs even when debugging is enabled since the frame
# pointer is no longer needed for debugging.
#
if fnmatch '-g*|*\ -g*' "$CFLAGS_AUTO $CFLAGS" ; then :
else 
tryflag CFLAGS_AUTO -fomit-frame-pointer
fi

#
# Modern GCC wants to put DWARF tables (used for debugging and
# unwinding) in the loaded part of the program where they are
# unstrippable. These options force them back to debug sections (and
# cause them not to get generated at all if debugging is off).
#
tryflag CFLAGS_AUTO -fno-unwind-tables
tryflag CFLAGS_AUTO -fno-asynchronous-unwind-tables

#
# Attempt to put each function and each data object in its own
# section. This both allows additional size optimizations at link
# time and works around a dangerous class of compiler/assembler bugs
# whereby relative address expressions are constant-folded by the
# assembler even when one or more of the symbols involved is
# replaceable. See gas pr 18561 and gcc pr 66609, 68178, etc.
#
tryflag CFLAGS_AUTO -ffunction-sections
tryflag CFLAGS_AUTO -fdata-sections

#
# On x86, make sure we don't have incompatible instruction set
# extensions enabled by default. This is bad for making static binaries.
# We cheat and use i486 rather than i386 because i386 really does not
# work anyway (issues with atomic ops).
# Some build environments pass -march and -mtune options via CC, so
# check both CC and CFLAGS.
#
if test "$ARCH" = "i386" ; then
fnmatch '-march=*|*\ -march=*' "$CC $CFLAGS" || tryldflag CFLAGS_AUTO -march=i486
fnmatch '-mtune=*|*\ -mtune=*' "$CC $CFLAGS" || tryldflag CFLAGS_AUTO -mtune=generic
fi

#
# GCC defines -w as overriding any -W options, regardless of order, but
# clang has a bunch of annoying warnings enabled by default and needs -w
# to start from a clean slate. So use -w if building with clang.
#
test "$cc_family" = clang && tryflag CFLAGS_AUTO -w

#
# Even with -std=c99, gcc accepts some constructs which are constraint
# violations. We want to treat these as errors regardless of whether
# other purely stylistic warnings are enabled -- especially implicit
# function declarations, which are a dangerous programming error.
#
tryflag CFLAGS_AUTO -Werror=implicit-function-declaration
tryflag CFLAGS_AUTO -Werror=implicit-int
tryflag CFLAGS_AUTO -Werror=pointer-sign
tryflag CFLAGS_AUTO -Werror=pointer-arith

#
# GCC ignores unused arguements by default, but Clang needs this extra
# parameter to stop printing warnings about LDFLAGS passed during
# compiling stage and CFLAGS passed during linking stage.
#
test "$cc_family" = clang && tryflag CFLAGS_AUTO -Qunused-arguments

if test "x$warnings" = xyes ; then
tryflag CFLAGS_AUTO -Wall
tryflag CFLAGS_AUTO -Wno-parentheses
tryflag CFLAGS_AUTO -Wno-uninitialized
tryflag CFLAGS_AUTO -Wno-missing-braces
tryflag CFLAGS_AUTO -Wno-unused-value
tryflag CFLAGS_AUTO -Wno-unused-but-set-variable
tryflag CFLAGS_AUTO -Wno-unknown-pragmas
tryflag CFLAGS_AUTO -Wno-pointer-to-int-cast
fi

# Determine if the compiler produces position-independent code (PIC)
# by default. If so, we don't need to compile separate object files
# for libc.a and libc.so.
if trycppif __PIC__ "$CFLAGS_C99FSE $CPPFLAGS $CFLAGS" ; then
pic_default=yes
else
pic_default=no
fi

# Reduce space lost to padding for alignment purposes by sorting data
# objects according to their alignment reqirements. This approximates
# optimal packing.
tryldflag LDFLAGS_AUTO -Wl,--sort-section,alignment
tryldflag LDFLAGS_AUTO -Wl,--sort-common

# When linking shared library, drop dummy weak definitions that were
# replaced by strong definitions from other translation units.
tryldflag LDFLAGS_AUTO -Wl,--gc-sections

# Some patched GCC builds have these defaults messed up...
tryldflag LDFLAGS_AUTO -Wl,--hash-style=both

# Prevent linking if there are undefined symbols; if any exist,
# libc.so will crash at runtime during relocation processing.
# The common way this can happen is failure to link the compiler
# runtime library; implementation error is also a possibility.
tryldflag LDFLAGS_AUTO -Wl,--no-undefined

# Avoid exporting symbols from compiler runtime libraries. They
# should be hidden anyway, but some toolchains including old gcc
# versions built without shared library support and pcc are broken.
tryldflag LDFLAGS_AUTO -Wl,--exclude-libs=ALL

# Public data symbols must be interposable to allow for copy
# relocations, but otherwise we want to bind symbols at libc link
# time to eliminate startup relocations and PLT overhead. Use
# --dynamic-list rather than -Bsymbolic-functions for greater
# control over what symbols are left unbound.
tryldflag LDFLAGS_AUTO -Wl,--dynamic-list="$srcdir/dynamic.list"

# Find compiler runtime library
test -z "$LIBCC" && tryldflag LIBCC -lgcc && tryldflag LIBCC -lgcc_eh
test -z "$LIBCC" && tryldflag LIBCC -lcompiler_rt
test -z "$LIBCC" && try_libcc=`$CC -print-libgcc-file-name 2>/dev/null` \
                 && tryldflag LIBCC "$try_libcc"
test -z "$LIBCC" && try_libcc=`$CC -print-file-name=libpcc.a 2>/dev/null` \
                 && tryldflag LIBCC "$try_libcc"
printf "using compiler runtime libraries: %s\n" "$LIBCC"

# Figure out arch variants for archs with variants
SUBARCH=
t="$CFLAGS_C99FSE $CPPFLAGS $CFLAGS"

if test "$ARCH" = "i386" ; then
printf "checking whether compiler can use ebx in PIC asm constraints... "
cat > "$tmpc" <<EOF
int foo(int x) { __asm__ ( "" : "+b"(x) ); return x; }
EOF
if $CC $CFLAGS_C99FSE $CPPFLAGS $CFLAGS -fPIC \
  -c -o /dev/null "$tmpc" >/dev/null 2>&1 ; then
printf "yes\n"
else
printf "no\n"
CFLAGS_AUTO="$CFLAGS_AUTO -DBROKEN_EBX_ASM"
fi
fi

if test "$ARCH" = "x86_64" ; then
trycppif __ILP32__ "$t" && ARCH=x32
fi

if test "$ARCH" = "arm" ; then
if trycppif __thumb2__ "$t" ; then
tryflag CFLAGS_AUTO -mimplicit-it=always
tryflag CFLAGS_AUTO -Wa,-mimplicit-it=always
tryflag CFLAGS_AUTO -Wa,-mthumb
fi
trycppif __ARMEB__ "$t" && SUBARCH=${SUBARCH}eb
trycppif __ARM_PCS_VFP "$t" && SUBARCH=${SUBARCH}hf
# Versions of clang up until at least 3.8 have the wrong constraint codes
# for floating point operands to inline asm. Detect this so the affected
# source files can just disable the asm.
if test "$cc_family" = clang ; then
printf "checking whether clang's vfp asm constraints work... "
echo 'float f(float x) { __asm__("":"+t"(x)); return x; }' > "$tmpc"
if $CC $CFLAGS_C99FSE $CPPFLAGS $CFLAGS -c -o /dev/null "$tmpc" >/dev/null 2>&1 ; then
printf "yes\n"
else
printf "no\n"
CFLAGS_AUTO="$CFLAGS_AUTO -DBROKEN_VFP_ASM"
CFLAGS_AUTO="${CFLAGS_AUTO# }"
fi
fi
fi

if test "$ARCH" = "aarch64" ; then
trycppif __AARCH64EB__ "$t" && SUBARCH=${SUBARCH}_be
fi

if test "$ARCH" = "m68k" ; then
if trycppif "__HAVE_68881__" ; then : ;
elif trycppif "__mcffpu__" ; then SUBARCH="-fp64"
else SUBARCH="-sf"
fi
fi

if test "$ARCH" = "mips" ; then
trycppif "__mips_isa_rev >= 6" "$t" && SUBARCH=${SUBARCH}r6
trycppif "_MIPSEL || __MIPSEL || __MIPSEL__" "$t" && SUBARCH=${SUBARCH}el
trycppif __mips_soft_float "$t" && SUBARCH=${SUBARCH}-sf
fi

if test "$ARCH" = "mips64" ; then
trycppif "_MIPS_SIM != _ABI64" "$t" && ARCH=mipsn32
trycppif "__mips_isa_rev >= 6" "$t" && SUBARCH=${SUBARCH}r6
trycppif "_MIPSEL || __MIPSEL || __MIPSEL__" "$t" && SUBARCH=${SUBARCH}el
trycppif __mips_soft_float "$t" && SUBARCH=${SUBARCH}-sf
fi

if test "$ARCH" = "powerpc" ; then
trycppif "__NO_FPRS__ && !_SOFT_FLOAT" "$t" && fail \
  "$0: error: compiler's floating point configuration is unsupported"
trycppif _SOFT_FLOAT "$t" && SUBARCH=${SUBARCH}-sf
printf "checking whether compiler can use 'd' constraint in asm... "
echo 'double f(double x) { __asm__ ("fabs %0, %1" : "=d"(x) : "d"(x)); return x; }' > "$tmpc"
if $CC $CFLAGS_C99FSE $CPPFLAGS $CFLAGS -c -o /dev/null "$tmpc" >/dev/null 2>&1 ; then
printf "yes\n"
else
printf "no\n"
CFLAGS_AUTO="$CFLAGS_AUTO -DBROKEN_PPC_D_ASM"
CFLAGS_AUTO="${CFLAGS_AUTO# }"
fi
fi

test "$ARCH" = "microblaze" && trycppif __MICROBLAZEEL__ "$t" \
&& SUBARCH=${SUBARCH}el

if test "$ARCH" = "powerpc64" ; then
trycppif "_CALL_ELF == 2" "$t" || fail "$0: error: unsupported powerpc64 ABI"
trycppif __LITTLE_ENDIAN__ "$t" && SUBARCH=${SUBARCH}le
trycppif _SOFT_FLOAT "$t" && fail "$0: error: soft-float not supported on powerpc64"
fi

if test "$ARCH" = "riscv64" ; then
trycppif __riscv_float_abi_soft "$t" && SUBARCH=${SUBARCH}-sf
trycppif __riscv_float_abi_single "$t" && SUBARCH=${SUBARCH}-sp
fi

if test "$ARCH" = "sh" ; then
tryflag CFLAGS_AUTO -Wa,--isa=any
trycppif __BIG_ENDIAN__ "$t" && SUBARCH=${SUBARCH}eb
if trycppif "__SH_FPU_ANY__ || __SH4__" "$t" ; then
# Some sh configurations are broken and replace double with float
# rather than using softfloat when the fpu is present but only
# supports single precision. Reject them.
printf "checking whether compiler's double type is IEEE double... "
echo 'typedef char dblcheck[(int)sizeof(double)-5];' > "$tmpc"
if $CC $CFLAGS_C99FSE $CPPFLAGS $CFLAGS -c -o /dev/null "$tmpc" >/dev/null 2>&1 ; then
printf "yes\n"
else
printf "no\n"
fail "$0: error: compiler's floating point configuration is unsupported"
fi
else
SUBARCH=${SUBARCH}-nofpu
fi
if trycppif __SH_FDPIC__ "$t" ; then
SUBARCH=${SUBARCH}-fdpic
fi
fi

test "$SUBARCH" \
&& printf "configured for %s variant: %s\n" "$ARCH" "$ARCH$SUBARCH"

case "$ARCH$SUBARCH" in
arm) ASMSUBARCH=el ;;
*) ASMSUBARCH=$SUBARCH ;;
esac

#
# Some archs (powerpc) have different possible long double formats
# that the compiler can be configured for. The logic for whether this
# is supported is in bits/float.h; in general, it is not. We need to
# check for mismatches here or code in printf, strotd, and scanf will
# be dangerously incorrect because it depends on (1) the macros being
# correct, and (2) IEEE semantics.
#
printf "checking whether compiler's long double definition matches float.h... "
echo '#include <float.h>' > "$tmpc"
echo '#define C(m,s) (m==LDBL_MANT_DIG && s==sizeof(long double))' >> "$tmpc"
echo 'typedef char ldcheck[(C(53,8)||C(64,12)||C(64,16)||C(113,16))*2-1];' >> "$tmpc"
if $CC $CFLAGS_C99FSE \
  -I$srcdir/arch/$ARCH -I$srcdir/arch/generic -I$srcdir/include \
  $CPPFLAGS $CFLAGS -c -o /dev/null "$tmpc" >/dev/null 2>&1 ; then
printf "yes\n"
else
printf "no\n"
fail "$0: error: unsupported long double type"
fi

#
# Some build systems globally pass in broken CFLAGS like -ffast-math
# for all packages. On recent GCC we can detect this and error out
# early rather than producing a seriously-broken math library.
#
if trycppif "__FAST_MATH__" \
  "$CFLAGS_C99FSE $CPPFLAGS $CFLAGS" ; then
fail "$0: error: compiler has broken floating point; check CFLAGS"
fi

printf "creating config.mak... "

cmdline=$(quote "$0")
for i ; do cmdline="$cmdline $(quote "$i")" ; done

exec 3>&1 1>config.mak


cat << EOF
# This version of config.mak was generated by:
# $cmdline
# Any changes made here will be lost if configure is re-run
AR = ${AR:-\$(CROSS_COMPILE)ar}
RANLIB = ${RANLIB:-\$(CROSS_COMPILE)ranlib}
ARCH = $ARCH
SUBARCH = $SUBARCH
ASMSUBARCH = $ASMSUBARCH
srcdir = $srcdir
prefix = $prefix
exec_prefix = $exec_prefix
bindir = $bindir
libdir = $libdir
includedir = $includedir
syslibdir = $syslibdir
CC = $CC
CFLAGS = $CFLAGS
CFLAGS_AUTO = $CFLAGS_AUTO
CFLAGS_C99FSE = $CFLAGS_C99FSE
CFLAGS_MEMOPS = $CFLAGS_MEMOPS
CFLAGS_NOSSP = $CFLAGS_NOSSP
CPPFLAGS = $CPPFLAGS
LDFLAGS = $LDFLAGS
LDFLAGS_AUTO = $LDFLAGS_AUTO
CROSS_COMPILE = $CROSS_COMPILE
LIBCC = $LIBCC
OPTIMIZE_GLOBS = $OPTIMIZE_GLOBS
ALL_TOOLS = $tools
TOOL_LIBS = $tool_libs
ADD_CFI = $ADD_CFI
MALLOC_DIR = $malloc_dir
EOF
test "x$static" = xno && echo "STATIC_LIBS ="
test "x$shared" = xno && echo "SHARED_LIBS ="
test "x$cc_family" = xgcc && echo 'WRAPCC_GCC = $(CC)'
test "x$cc_family" = xclang && echo 'WRAPCC_CLANG = $(CC)'
test "x$pic_default" = xyes && echo 'AOBJS = $(LOBJS)'
exec 1>&3 3>&-

test "$srcdir" = "." || ln -sf $srcdir/Makefile .

printf "done\n"