nixpkgs/pkgs/build-support/cc-wrapper/ld-wrapper.sh
2017-11-05 12:19:37 +02:00

206 lines
6.4 KiB
Bash

#! @shell@
set -eu -o pipefail +o posix
shopt -s nullglob
if (( "${NIX_DEBUG:-0}" >= 7 )); then
set -x
fi
path_backup="$PATH"
# phase separation makes this look useless
# shellcheck disable=SC2157
if [ -n "@coreutils_bin@" ]; then
PATH="@coreutils_bin@/bin"
fi
if [ -z "${NIX_CC_WRAPPER_@infixSalt@_FLAGS_SET:-}" ]; then
source @out@/nix-support/add-flags.sh
fi
source @out@/nix-support/utils.sh
# Optionally filter out paths not refering to the store.
expandResponseParams "$@"
if [[ "${NIX_ENFORCE_PURITY:-}" = 1 && -n "${NIX_STORE:-}"
&& ( -z "$NIX_@infixSalt@_IGNORE_LD_THROUGH_GCC" || -z "${NIX_@infixSalt@_LDFLAGS_SET:-}" ) ]]; then
rest=()
nParams=${#params[@]}
declare -i n=0
while (( "$n" < "$nParams" )); do
p=${params[n]}
p2=${params[n+1]:-} # handle `p` being last one
if [ "${p:0:3}" = -L/ ] && badPath "${p:2}"; then
skip "${p:2}"
elif [ "$p" = -L ] && badPath "$p2"; then
n+=1; skip "$p2"
elif [ "$p" = -rpath ] && badPath "$p2"; then
n+=1; skip "$p2"
elif [ "$p" = -dynamic-linker ] && badPath "$p2"; then
n+=1; skip "$p2"
elif [ "${p:0:1}" = / ] && badPath "$p"; then
# We cannot skip this; barf.
echo "impure path \`$p' used in link" >&2
exit 1
elif [ "${p:0:9}" = --sysroot ]; then
# Our ld is not built with sysroot support (Can we fix that?)
:
else
rest+=("$p")
fi
n+=1
done
# Old bash empty array hack
params=(${rest+"${rest[@]}"})
fi
source @out@/nix-support/add-hardening.sh
extraAfter=("${hardeningLDFlags[@]}")
extraBefore=()
if [ -z "${NIX_@infixSalt@_LDFLAGS_SET:-}" ]; then
extraAfter+=($NIX_@infixSalt@_LDFLAGS)
extraBefore+=($NIX_@infixSalt@_LDFLAGS_BEFORE)
fi
extraAfter+=($NIX_@infixSalt@_LDFLAGS_AFTER)
# Three tasks:
#
# 1. Find all -L... switches for rpath
#
# 2. Find relocatable flag for build id.
#
# 3. Choose 32-bit dynamic linker if needed
declare -a libDirs
declare -A libs
declare -i relocatable=0 link32=0
if
[ "$NIX_@infixSalt@_DONT_SET_RPATH" != 1 ] \
|| [ "$NIX_@infixSalt@_SET_BUILD_ID" = 1 ] \
|| [ -e @out@/nix-support/dynamic-linker-m32 ]
then
prev=
# Old bash thinks empty arrays are undefined, ugh.
for p in \
${extraBefore+"${extraBefore[@]}"} \
${params+"${params[@]}"} \
${extraAfter+"${extraAfter[@]}"}
do
case "$prev" in
-L)
libDirs+=("$p")
;;
-l)
libs["lib${p}.so"]=1
;;
-m)
# Presumably only the last `-m` flag has any effect.
case "$p" in
elf_i386) link32=1;;
*) link32=0;;
esac
;;
-dynamic-linker | -plugin)
# Ignore this argument, or it will match *.so and be added to rpath.
;;
*)
case "$p" in
-L/*)
libDirs+=("${p:2}")
;;
-l?*)
libs["lib${p:2}.so"]=1
;;
"${NIX_STORE:-}"/*.so | "${NIX_STORE:-}"/*.so.*)
# This is a direct reference to a shared library.
libDirs+=("${p%/*}")
libs["${p##*/}"]=1
;;
-r | --relocatable | -i)
relocatable=1
esac
;;
esac
prev="$p"
done
fi
if [ -e "@out@/nix-support/dynamic-linker-m32" ] && (( "$link32" )); then
# We have an alternate 32-bit linker and we're producing a 32-bit ELF, let's
# use it.
extraAfter+=(
'-dynamic-linker'
"$(< @out@/nix-support/dynamic-linker-m32)"
)
fi
# Add all used dynamic libraries to the rpath.
if [ "$NIX_@infixSalt@_DONT_SET_RPATH" != 1 ]; then
# For each directory in the library search path (-L...),
# see if it contains a dynamic library used by a -l... flag. If
# so, add the directory to the rpath.
# It's important to add the rpath in the order of -L..., so
# the link time chosen objects will be those of runtime linking.
declare -A rpaths
for dir in ${libDirs+"${libDirs[@]}"}; do
if [[ "$dir" =~ [/.][/.] ]] && dir2=$(readlink -f "$dir"); then
dir="$dir2"
fi
if [ -n "${rpaths[$dir]:-}" ] || [[ "$dir" != "${NIX_STORE:-}"/* ]]; then
# If the path is not in the store, don't add it to the rpath.
# This typically happens for libraries in /tmp that are later
# copied to $out/lib. If not, we're screwed.
continue
fi
for path in "$dir"/*; do
file="${path##*/}"
if [ "${libs[$file]:-}" ]; then
# This library may have been provided by a previous directory,
# but if that library file is inside an output of the current
# derivation, it can be deleted after this compilation and
# should be found in a later directory, so we add all
# directories that contain any of the libraries to rpath.
rpaths["$dir"]=1
extraAfter+=(-rpath "$dir")
break
fi
done
done
fi
# This is outside the DONT_SET_RPATH branch because it's more targeted and we
# usually want it (on Darwin) even if DONT_SET_RPATH is set.
if [ -n "${NIX_COREFOUNDATION_RPATH:-}" ]; then
extraAfter+=(-rpath $NIX_COREFOUNDATION_RPATH)
fi
# Only add --build-id if this is a final link. FIXME: should build gcc
# with --enable-linker-build-id instead?
if [ "$NIX_@infixSalt@_SET_BUILD_ID" = 1 ] && ! (( "$relocatable" )); then
extraAfter+=(--build-id)
fi
# Optionally print debug info.
if (( "${NIX_DEBUG:-0}" >= 1 )); then
# Old bash workaround, see above.
echo "extra flags before to @prog@:" >&2
printf " %q\n" ${extraBefore+"${extraBefore[@]}"} >&2
echo "original flags to @prog@:" >&2
printf " %q\n" ${params+"${params[@]}"} >&2
echo "extra flags after to @prog@:" >&2
printf " %q\n" ${extraAfter+"${extraAfter[@]}"} >&2
fi
PATH="$path_backup"
# Old bash workaround, see above.
exec @prog@ \
${extraBefore+"${extraBefore[@]}"} \
${params+"${params[@]}"} \
${extraAfter+"${extraAfter[@]}"}