usage () {
cat <<EOF
-Usage: $0 [OPTION]... [VAR=VALUE]... [BUILDTYPE]
+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.
System types:
--target=TARGET configure to run on target TARGET [detected]
- --build=BUILD same as --target
+ --host=HOST same as --target
Optional features:
--enable-debug build with debugging information [disabled]
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.
cmdexists () { type "$1" >/dev/null 2>&1 ; }
trycc () { test -z "$CC" && cmdexists "$1" && CC=$1 ; }
-setdir () {
-if eval "test -z \"\${$1}\"" ; then eval "$1=\$2"
-else eval "fnmatch '*/' \"\${$1}\"" && eval "$1=\${$1%/}" ; fi
+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" "$2" -c -o /dev/null "$tmpc" 2>/dev/null ; then
+if $CC "$2" -c -o /dev/null "$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 -nostdlib -shared "$2" -o /dev/null "$tmpc" >/dev/null 2>&1 ; then
printf "yes\n"
eval "$1=\"\${$1} \$2\""
eval "$1=\${$1# }"
# Beginning of actual script
-prefix=
-exec_prefix=
-bindir=
-libdir=
-includedir=
-syslibdir=
-build=
+CFLAGS_C99FSE=
+CFLAGS_AUTO=
+LDFLAGS_AUTO=
+prefix=/usr/local/musl
+exec_prefix='$(prefix)'
+bindir='$(exec_prefix)/bin'
+libdir='$(prefix)/lib'
+includedir='$(prefix)/include'
+syslibdir='/lib'
+target=
debug=no
-warnings=
+warnings=no
shared=yes
static=yes
--disable-warnings|--enable-warnings=no) warnings=no ;;
--enable-gcc-wrapper|--enable-gcc-wrapper=yes) wrapper=yes ;;
--disable-gcc-wrapper|--enable-gcc-wrapper=no) wrapper=no ;;
---enable-*|--disable-*|--with-*|--without-*|--*dir=*|--host=*) ;;
---build=*|--target=*) build=${arg#*=} ;;
+--enable-*|--disable-*|--with-*|--without-*|--*dir=*|--build=*) ;;
+--host=*|--target=*) target=${arg#*=} ;;
-* ) echo "$0: unknown option $arg" ;;
CC=*) CC=${arg#*=} ;;
CFLAGS=*) CFLAGS=${arg#*=} ;;
CPPFLAGS=*) CPPFLAGS=${arg#*=} ;;
LDFLAGS=*) LDFLAGS=${arg#*=} ;;
-*) build=$arg ;;
+CROSS_COMPILE=*) CROSS_COMPILE=${arg#*=} ;;
+LIBCC=*) LIBCC=${arg#*=} ;;
+*=*) ;;
+*) target=$arg ;;
esac
done
-setdir prefix /usr/local/musl
-setdir exec_prefix '$(prefix)'
-setdir bindir '$(exec_prefix)/bin'
-setdir libdir '$(prefix)/lib'
-setdir includedir '$(prefix)/include'
-setdir syslibdir '/lib'
+for i in prefix exec_prefix bindir libdir includedir syslibdir ; do
+stripdir $i
+done
#
# Get a temp filename we can use
set -C
while : ; do i=$(($i+1))
tmpc="./conf$$-$PPID-$i.c"
-2>/dev/null > "$tmpc" && break
+2>|/dev/null > "$tmpc" && break
test "$i" -gt 50 && fail "$0: cannot create temporary file $tmpc"
done
set +C
# Find a C compiler to use
#
printf "checking for C compiler... "
-trycc gcc
-trycc c99
-trycc cc
+trycc ${CROSS_COMPILE}gcc
+trycc ${CROSS_COMPILE}c99
+trycc ${CROSS_COMPILE}cc
printf "%s\n" "$CC"
test -n "$CC" || { echo "$0: cannot find a C compiler" ; exit 1 ; }
#
if test -z "$wrapper" ; then
printf "checking whether compiler is gcc... "
-if fnmatch 'gcc*|GCC*' "$("$CC" --version 2>/dev/null)" ; then
+if fnmatch '*gcc\ version*' "$($CC -v 2>&1)" ; then
echo yes
printf "checking whether to build musl-gcc wrapper... "
wrapper=yes
#
-# Find the build architecture
+# Find the target architecture
#
-printf "checking build system type... "
-test -n "$build" || build=$("$CC" -dumpmachine 2>/dev/null) || build=unknown
-printf "%s\n" "$build"
+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 "$build" in
+case "$target" in
arm*) ARCH=arm ;;
i?86*) ARCH=i386 ;;
x86_64*) ARCH=x86_64 ;;
-unknown) fail "$0: unable to detect built target; try $0 --build=..." ;;
-*) fail "$0: unknown or unsupported build target \"$build\"" ;;
+mips-*|mipsel-*) ARCH=mips ;;
+microblaze-*) ARCH=microblaze ;;
+powerpc-*) ARCH=powerpc ;;
+unknown) fail "$0: unable to detect target arch; try $0 --target=..." ;;
+*) fail "$0: unknown or unsupported target \"$target\"" ;;
esac
#
tryflag CFLAGS_C99FSE -ffreestanding \
|| tryflag CFLAGS_C99FSE -fno-builtin
tryflag CFLAGS_C99FSE -fexcess-precision=standard \
-|| tryflag CFLAGS_C99FSE -ffloat-store
+|| { test "$ARCH" = i386 && tryflag CFLAGS_C99FSE -ffloat-store ; }
tryflag CFLAGS_C99FSE -frounding-math
#
tryflag CFLAGS_AUTO -pipe
#
-# If debugging is disabled, omit bloated DWARF2 unwind tables & frame ptr
+# If debugging is disabled, omit frame pointer. Modern GCC does this
+# anyway on most archs even when debugging is enabled since the frame
+# pointer is no longer needed for debugging.
#
if fnmatch '-g*|*\ -g*' "$CFLAGS_AUTO $CFLAGS" ; then :
else
-tryflag CFLAGS_AUTO -fno-unwind-tables
-tryflag CFLAGS_AUTO -fno-asynchronous-unwind-tables
tryflag CFLAGS_AUTO -fomit-frame-pointer
fi
+#
+# Modern GCC wants to put DWARF tables (used for debugging and
+# unwinding) in the loaded part of the program where they are
+# unstrippable. These options force them back to debug sections (and
+# cause them not to get generated at all if debugging is off).
+#
+tryflag CFLAGS_AUTO -fno-unwind-tables
+tryflag CFLAGS_AUTO -fno-asynchronous-unwind-tables
+
+#
+# The GNU toolchain defaults to assuming unmarked files need an
+# executable stack, potentially exposing vulnerabilities in programs
+# linked with such object files. Fix this.
+#
+tryflag CFLAGS_AUTO -Wa,--noexecstack
+
#
# Some optimization levels add bloated alignment that hurt performance
#
# work anyway (issues with atomic ops).
#
if test "$ARCH" = "i386" ; then
-fnmatch '-march=*|*\ -march=*' "$CFLAGS" || tryflag CFLAGS_AUTO -march=i486
-fnmatch '-mtune=*|*\ -mtune=*' "$CFLAGS" || tryflag CFLAGS_AUTO -mtune=generic
+fnmatch '-march=*|*\ -march=*' "$CFLAGS" || tryldflag CFLAGS_AUTO -march=i486
+fnmatch '-mtune=*|*\ -mtune=*' "$CFLAGS" || tryldflag CFLAGS_AUTO -mtune=generic
fi
+#
+# 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
+
if test "x$warnings" = xyes ; then
tryflag CFLAGS_AUTO -Wall
-tryflag CFLAGS_AUTO -Wpointer-arith
tryflag CFLAGS_AUTO -Wcast-align
tryflag CFLAGS_AUTO -Wno-parentheses
tryflag CFLAGS_AUTO -Wno-uninitialized
tryflag CFLAGS_AUTO -Wno-unknown-pragmas
fi
+# Some patched GCC builds have these defaults messed up...
+tryflag CFLAGS_AUTO -fno-stack-protector
+tryldflag LDFLAGS_AUTO -Wl,--hash-style=both
+
+# Disable dynamic linking if ld is broken and can't do -Bsymbolic-functions
+LDFLAGS_DUMMY=
+tryldflag LDFLAGS_DUMMY -Wl,-Bsymbolic-functions || {
+printf "warning: disabling dynamic linking support\n"
+shared=no
+}
+
+# Find compiler runtime library
+test -z "$LIBCC" && tryldflag LIBCC -lgcc && tryldflag LIBCC -lgcc_eh
+test -z "$LIBCC" && tryldflag LIBCC -lcompiler_rt
+test -z "$LIBCC" && try_libcc=`$CC -print-file-name=libpcc.a 2>/dev/null` \
+ && tryldflag LIBCC "$try_libcc"
+printf "using compiler runtime libraries: %s\n" "$LIBCC"
+
+# Figure out arch variants for archs with variants
+SUBARCH=
+t="$CFLAGS_C99FSE $CPPFLAGS $CFLAGS_AUTO $CFLAGS"
+
+if test "$ARCH" = "arm" ; then
+trycppif __ARMEB__ "$t" && SUBARCH=${SUBARCH}eb
+trycppif __SOFTFP__ "$t" || SUBARCH=${SUBARCH}hf
+fi
+
+test "$ARCH" = "mips" && trycppif "_MIPSEL || __MIPSEL || __MIPSEL__" "$t" \
+&& SUBARCH=${SUBARCH}el
+
+test "$ARCH" = "microblaze" && trycppif __MICROBLAZEEL__ "$t" \
+&& SUBARCH=${SUBARCH}el
+
+test "$SUBARCH" \
+&& printf "configured for %s variant: %s\n" "$ARCH" "$ARCH$SUBARCH"
printf "creating config.mak... "
# This version of config.mak was generated by configure
# Any changes made here will be lost if configure is re-run
ARCH = $ARCH
+SUBARCH = $SUBARCH
prefix = $prefix
exec_prefix = $exec_prefix
bindir = $bindir
CFLAGS= $CFLAGS_AUTO $CFLAGS
CFLAGS_C99FSE = $CFLAGS_C99FSE
CPPFLAGS = $CPPFLAGS
-LDFLAGS = $LDFLAGS
+LDFLAGS = $LDFLAGS_AUTO $LDFLAGS
+CROSS_COMPILE = $CROSS_COMPILE
+LIBCC = $LIBCC
EOF
test "x$static" = xno && echo "STATIC_LIBS ="
test "x$shared" = xno && echo "SHARED_LIBS ="