nixpkgs/pkgs/build-support/cc-wrapper/cc-wrapper.sh
Emily e047c69ed4 {bintools-wrapper,cc-wrapper}: allow paths relative to the Darwin SDK
`-L` and `-I` are interpreted relative to the `$SDKROOT` by the
Darwin toolchain, so we have to avoid filtering out such paths in the
purity filter hacks in order to not break e.g. the .NET Core build
system. It’s also just the correct thing to do for the platform.
2024-10-26 15:28:50 +01:00

269 lines
8.7 KiB
Bash

#! @shell@
set -eu -o pipefail +o posix
shopt -s nullglob
if (( "${NIX_DEBUG:-0}" >= 7 )); then
set -x
fi
path_backup="$PATH"
# That @-vars are substituted separately from bash evaluation makes
# shellcheck think this, and others like it, are useless conditionals.
# shellcheck disable=SC2157
if [[ -n "@coreutils_bin@" && -n "@gnugrep_bin@" ]]; then
PATH="@coreutils_bin@/bin:@gnugrep_bin@/bin"
fi
source @out@/nix-support/utils.bash
source @out@/nix-support/darwin-sdk-setup.bash
# Parse command line options and set several variables.
# For instance, figure out if linker flags should be passed.
# GCC prints annoying warnings when they are not needed.
dontLink=0
nonFlagArgs=0
cc1=0
# shellcheck disable=SC2193
[[ "@prog@" = *++ ]] && isCxx=1 || isCxx=0
cxxInclude=1
cxxLibrary=1
cInclude=1
expandResponseParams "$@"
declare -ag positionalArgs=()
declare -i n=0
nParams=${#params[@]}
while (( "$n" < "$nParams" )); do
p=${params[n]}
p2=${params[n+1]:-} # handle `p` being last one
n+=1
case "$p" in
-[cSEM] | -MM) dontLink=1 ;;
-cc1) cc1=1 ;;
-nostdinc) cInclude=0 cxxInclude=0 ;;
-nostdinc++) cxxInclude=0 ;;
-nostdlib) cxxLibrary=0 ;;
-x*-header) dontLink=1 ;; # both `-x c-header` and `-xc-header` are accepted by clang
-xc++*) isCxx=1 ;; # both `-xc++` and `-x c++` are accepted by clang
-x)
case "$p2" in
*-header) dontLink=1 ;;
c++*) isCxx=1 ;;
esac
;;
--) # Everything else is positional args!
# See: https://github.com/llvm/llvm-project/commit/ed1d07282cc9d8e4c25d585e03e5c8a1b6f63a74
# Any positional arg (i.e. any argument after `--`) will be
# interpreted as a "non flag" arg:
if [[ -v "params[$n]" ]]; then nonFlagArgs=1; fi
positionalArgs=("${params[@]:$n}")
params=("${params[@]:0:$((n - 1))}")
break;
;;
-?*) ;;
*) nonFlagArgs=1 ;; # Includes a solitary dash (`-`) which signifies standard input; it is not a flag
esac
done
# If we pass a flag like -Wl, then gcc will call the linker unless it
# can figure out that it has to do something else (e.g., because of a
# "-c" flag). So if no non-flag arguments are given, don't pass any
# linker flags. This catches cases like "gcc" (should just print
# "gcc: no input files") and "gcc -v" (should print the version).
if [ "$nonFlagArgs" = 0 ]; then
dontLink=1
fi
# Arocc does not link
if [ "@isArocc@" = 1 ]; then
dontLink=1
fi
# Optionally filter out paths not refering to the store.
if [[ "${NIX_ENFORCE_PURITY:-}" = 1 && -n "$NIX_STORE" ]]; then
kept=()
nParams=${#params[@]}
declare -i n=0
while (( "$n" < "$nParams" )); do
p=${params[n]}
p2=${params[n+1]:-} # handle `p` being last one
n+=1
skipNext=false
path=""
case "$p" in
-[IL]/*) path=${p:2} ;;
-[IL] | -isystem) path=$p2 skipNext=true ;;
esac
if [[ -n $path ]] && badPathWithDarwinSdk "$path"; then
skip "$path"
$skipNext && n+=1
continue
fi
kept+=("$p")
done
# Old bash empty array hack
params=(${kept+"${kept[@]}"})
fi
# Flirting with a layer violation here.
if [ -z "${NIX_BINTOOLS_WRAPPER_FLAGS_SET_@suffixSalt@:-}" ]; then
source @bintools@/nix-support/add-flags.sh
fi
# Put this one second so libc ldflags take priority.
if [ -z "${NIX_CC_WRAPPER_FLAGS_SET_@suffixSalt@:-}" ]; then
source @out@/nix-support/add-flags.sh
fi
# Clear march/mtune=native -- they bring impurity.
if [ "$NIX_ENFORCE_NO_NATIVE_@suffixSalt@" = 1 ]; then
kept=()
# Old bash empty array hack
for p in ${params+"${params[@]}"}; do
if [[ "$p" = -m*=native ]]; then
skip "$p"
else
kept+=("$p")
fi
done
# Old bash empty array hack
params=(${kept+"${kept[@]}"})
fi
if [[ "$isCxx" = 1 ]]; then
if [[ "$cxxInclude" = 1 ]]; then
#
# The motivation for this comment is to explain the reason for appending
# the C++ stdlib to NIX_CFLAGS_COMPILE, which I initially thought should
# change and later realized it shouldn't in:
#
# https://github.com/NixOS/nixpkgs/pull/185569#issuecomment-1234959249
#
# NIX_CFLAGS_COMPILE contains dependencies added using "-isystem", and
# NIX_CXXSTDLIB_COMPILE adds the C++ stdlib using "-isystem". Appending
# NIX_CXXSTDLIB_COMPILE to NIX_CLAGS_COMPILE emulates this part of the
# include lookup order from GCC/Clang:
#
# > 4. Directories specified with -isystem options are scanned in
# > left-to-right order.
# > 5. Standard system directories are scanned.
# > 6. Directories specified with -idirafter options are scanned
# > in left-to-right order.
#
# NIX_CXX_STDLIB_COMPILE acts as the "standard system directories" that
# are otherwise missing from CC in nixpkgs, so should be added last.
#
# This means that the C standard library should never be present inside
# NIX_CFLAGS_COMPILE, because it MUST come after the C++ stdlib. It is
# added automatically by cc-wrapper later using "-idirafter".
#
NIX_CFLAGS_COMPILE_@suffixSalt@+=" $NIX_CXXSTDLIB_COMPILE_@suffixSalt@"
fi
if [[ "$cxxLibrary" = 1 ]]; then
NIX_CFLAGS_LINK_@suffixSalt@+=" $NIX_CXXSTDLIB_LINK_@suffixSalt@"
fi
fi
source @out@/nix-support/add-hardening.sh
# Add the flags for the C compiler proper.
extraAfter=(${hardeningCFlagsAfter[@]+"${hardeningCFlagsAfter[@]}"} $NIX_CFLAGS_COMPILE_@suffixSalt@)
extraBefore=(${hardeningCFlagsBefore[@]+"${hardeningCFlagsBefore[@]}"} $NIX_CFLAGS_COMPILE_BEFORE_@suffixSalt@)
if [ "$dontLink" != 1 ]; then
linkType=$(checkLinkType $NIX_LDFLAGS_BEFORE_@suffixSalt@ "${params[@]}" ${NIX_CFLAGS_LINK_@suffixSalt@:-} $NIX_LDFLAGS_@suffixSalt@)
# Add the flags that should only be passed to the compiler when
# linking.
extraAfter+=($(filterRpathFlags "$linkType" $NIX_CFLAGS_LINK_@suffixSalt@))
# Add the flags that should be passed to the linker (and prevent
# `ld-wrapper' from adding NIX_LDFLAGS_@suffixSalt@ again).
for i in $(filterRpathFlags "$linkType" $NIX_LDFLAGS_BEFORE_@suffixSalt@); do
extraBefore+=("-Wl,$i")
done
if [[ "$linkType" == dynamic && -n "$NIX_DYNAMIC_LINKER_@suffixSalt@" ]]; then
extraBefore+=("-Wl,-dynamic-linker=$NIX_DYNAMIC_LINKER_@suffixSalt@")
fi
for i in $(filterRpathFlags "$linkType" $NIX_LDFLAGS_@suffixSalt@); do
if [ "${i:0:3}" = -L/ ]; then
extraAfter+=("$i")
else
extraAfter+=("-Wl,$i")
fi
done
export NIX_LINK_TYPE_@suffixSalt@=$linkType
fi
if [[ -e @out@/nix-support/add-local-cc-cflags-before.sh ]]; then
source @out@/nix-support/add-local-cc-cflags-before.sh
fi
# As a very special hack, if the arguments are just `-v', then don't
# add anything. This is to prevent `gcc -v' (which normally prints
# out the version number and returns exit code 0) from printing out
# `No input files specified' and returning exit code 1.
if [ "$*" = -v ]; then
extraAfter=()
extraBefore=()
fi
# clang's -cc1 mode is not compatible with most options
# that we would pass. Rather than trying to pass only
# options that would work, let's just remove all of them.
if [ "$cc1" = 1 ]; then
extraAfter=()
extraBefore=()
fi
# Finally, if we got any positional args, append them to `extraAfter`
# now:
if [[ "${#positionalArgs[@]}" -gt 0 ]]; then
extraAfter+=(-- "${positionalArgs[@]}")
fi
# Optionally print debug info.
if (( "${NIX_DEBUG:-0}" >= 1 )); then
# Old bash workaround, see ld-wrapper for explanation.
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="$path_backup"
# Old bash workaround, see above.
# if a cc-wrapper-hook exists, run it.
if [[ -e @out@/nix-support/cc-wrapper-hook ]]; then
compiler=@prog@
source @out@/nix-support/cc-wrapper-hook
fi
if (( "${NIX_CC_USE_RESPONSE_FILE:-@use_response_file_by_default@}" >= 1 )); then
responseFile=$(@mktemp@ "${TMPDIR:-/tmp}/cc-params.XXXXXX")
trap '@rm@ -f -- "$responseFile"' EXIT
printf "%q\n" \
${extraBefore+"${extraBefore[@]}"} \
${params+"${params[@]}"} \
${extraAfter+"${extraAfter[@]}"} > "$responseFile"
@prog@ "@$responseFile"
else
exec @prog@ \
${extraBefore+"${extraBefore[@]}"} \
${params+"${params[@]}"} \
${extraAfter+"${extraAfter[@]}"}
fi