static=yes
wrapper=auto
gcc_wrapper=no
+clang_wrapper=no
for arg ; do
case "$arg" in
--enable-visibility|--enable-visibility=yes) visibility=yes ;;
--disable-visibility|--enable-visibility=no) visibility=no ;;
--enable-wrapper|--enable-wrapper=yes) wrapper=detect ;;
---enable-wrapper=all) wrapper=yes ; gcc_wrapper=yes ;;
+--enable-wrapper=all) wrapper=yes ; gcc_wrapper=yes ; clang_wrapper=yes ;;
--enable-wrapper=gcc) wrapper=yes ; gcc_wrapper=yes ;;
+--enable-wrapper=clang) wrapper=yes ; clang_wrapper=yes ;;
--disable-wrapper|--enable-wrapper=no) wrapper=no ;;
--enable-gcc-wrapper|--enable-gcc-wrapper=yes) wrapper=yes ; gcc_wrapper=yes ;;
--disable-gcc-wrapper|--enable-gcc-wrapper=no) wrapper=no ;;
cc_family=unknown
if fnmatch '*gcc\ version*' "$cc_ver" ; then
cc_family=gcc
+elif fnmatch '*clang\ version*' "$cc_ver" ; then
+cc_family=clang
fi
echo "$cc_family"
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 "$wrapper" = detect ; then
tools="$tools tools/musl-gcc"
tool_libs="$tool_libs lib/musl-gcc.specs"
fi
+if test "$clang_wrapper" = yes ; then
+tools="$tools tools/musl-clang tools/ld.musl-clang"
+fi
#
# Find the target architecture
CFLAGS_C99FSE="$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,
#
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.
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.
+# 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 -Wa,--noexecstack
+tryflag CFLAGS_AUTO -ffunction-sections
+tryflag CFLAGS_AUTO -fdata-sections
#
# On x86, make sure we don't have incompatible instruction set
# - the -include option
# - the attributes/pragmas used in vis.h
# - linking code that takes the address of protected symbols
+# - gcc 3.x bug that wrongly claims declarations mismatch
printf "checking whether global visibility preinclude works... "
-echo 'int (*fp)(void);' > "$tmpc"
-echo 'int foo(void) { }' >> "$tmpc"
-echo 'int bar(void) { fp = foo; return foo(); }' >> "$tmpc"
+cat > "$tmpc" <<EOF
+__attribute__((__visibility__("default")))
+extern struct a *const x;
+typedef struct a b;
+extern b *const x;
+b *const x;
+int (*fp)(void);
+int foo(void) { }
+int bar(void) { fp = foo; return foo(); }
+EOF
if $CC $CFLAGS_C99FSE $CPPFLAGS $CFLAGS \
-DSHARED -fPIC -I./src/internal -include vis.h \
-nostdlib -shared -Wl,-Bsymbolic-functions \
CFLAGS_AUTO="${CFLAGS_AUTO# }"
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
+
test "$shared" = "no" || {
# Disable dynamic linking if ld is broken and can't do -Bsymbolic-functions
LDFLAGS_DUMMY=
&& SUBARCH=${SUBARCH}el
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
else
SUBARCH=${SUBARCH}-nofpu
fi
+if trycppif __SH_FDPIC__ "$t" ; then
+SUBARCH=${SUBARCH}-fdpic
+fi
fi
test "$SUBARCH" \
includedir = $includedir
syslibdir = $syslibdir
CC = $CC
-CFLAGS = $CFLAGS_AUTO $CFLAGS
+CFLAGS = $CFLAGS
+CFLAGS_AUTO = $CFLAGS_AUTO
CFLAGS_C99FSE = $CFLAGS_C99FSE
CFLAGS_MEMOPS = $CFLAGS_MEMOPS
CFLAGS_NOSSP = $CFLAGS_NOSSP
CPPFLAGS = $CPPFLAGS
-LDFLAGS = $LDFLAGS_AUTO $LDFLAGS
+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 = $ADD_CFI
EOF
test "x$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)'
exec 1>&3 3>&-
printf "done\n"