pkgs/build-support/setup-hooks/separate-debug-info.sh

   1 export NIX_SET_BUILD_ID=1
   2 export NIX_LDFLAGS+=" --compress-debug-sections=zlib"
   3 export NIX_CFLAGS_COMPILE+=" -ggdb -Wa,--compress-debug-sections"
   4 export NIX_RUSTFLAGS+=" -g -C strip=none"
   5
   6 fixupOutputHooks+=(_separateDebugInfo)
   7
   8 _separateDebugInfo() {
   9     [ -e "$prefix" ] || return 0
  10
  11     local dst="${debug:-$out}"
  12     if [ "$prefix" = "$dst" ]; then return 0; fi
  13
  14     # in case there is nothing to strip, don't fail the build
  15     mkdir -p "$dst"
  16
  17     dst="$dst/lib/debug/.build-id"
  18
  19     # Find executables and dynamic libraries.
  20     local i
  21     while IFS= read -r -d $'\0' i; do
  22         if ! isELF "$i"; then continue; fi
  23
  24         [ -z "${READELF:-}" ] && echo "_separateDebugInfo: '\$READELF' variable is empty, skipping." 1>&2 && break
  25         [ -z "${OBJCOPY:-}" ] && echo "_separateDebugInfo: '\$OBJCOPY' variable is empty, skipping." 1>&2 && break
  26
  27         # Extract the Build ID. FIXME: there's probably a cleaner way.
  28         local id="$($READELF -n "$i" | sed 's/.*Build ID: \([0-9a-f]*\).*/\1/; t; d')"
  29         if [ "${#id}" != 40 ]; then
  30             echo "could not find build ID of $i, skipping" >&2
  31             continue
  32         fi
  33
  34         # Extract the debug info.
  35         echo "separating debug info from $i (build ID $id)"
  36         mkdir -p "$dst/${id:0:2}"
  37
  38         # This may fail, e.g. if the binary is for a different
  39         # architecture than we're building for.  (This happens with
  40         # firmware blobs in QEMU.)
  41         (
  42             if [ -f "$dst/${id:0:2}/${id:2}.debug" ]
  43             then
  44                 echo "separate-debug-info: warning: multiple files with build id $id found, overwriting"
  45             fi
  46             $OBJCOPY --only-keep-debug "$i" "$dst/${id:0:2}/${id:2}.debug"
  47
  48             # Also a create a symlink <original-name>.debug.
  49             ln -sfn ".build-id/${id:0:2}/${id:2}.debug" "$dst/../$(basename "$i")"
  50         ) || rmdir -p "$dst/${id:0:2}"
  51     done < <(find "$prefix" -type f -print0 | sort -z)
  52 }