From: Alvin Šipraga <alsi@xxxxxxxxxxxxxxx>
Bash process substitution of the form `foo < <(bar)`, as found in
scripts/check-local-export, can cause issues in chrooted environments
and with tools such as pseudo. The blamed commit started to cause build
errors for me when using the Yocto project's devshell environment;
devshell uses pseudo internally:
.../scripts/check-local-export: line 51: /dev/fd/63: No such file or directory
Replace the process substitution with a simple pipe into the while loop.
This is functionally equivalent and more portable than the former. Note
that pipefail is enabled so that the script terminates when ${NM} fails.
Link: https://bugzilla.yoctoproject.org/show_bug.cgi?id=13288
Fixes: 31cb50b5590f ("kbuild: check static EXPORT_SYMBOL* by script instead of modpost")
Signed-off-by: Alvin Šipraga <alsi@xxxxxxxxxxxxxxx>
---
scripts/check-local-export | 28 +++++++++++++---------------
1 file changed, 13 insertions(+), 15 deletions(-)
diff --git a/scripts/check-local-export b/scripts/check-local-export
index da745e2743b7..42de6f8f2541 100755
--- a/scripts/check-local-export
+++ b/scripts/check-local-export
@@ -7,12 +7,24 @@
# EXPORT_SYMBOL should be used for global symbols.
set -e
+set -o pipefail
declare -A symbol_types
declare -a export_symbols
exit_code=0
+# If there is no symbol in the object, ${NM} (both GNU nm and llvm-nm)
+# shows 'no symbols' diagnostic (but exits with 0). It is harmless and
+# hidden by '2>/dev/null'. However, it suppresses real error messages
+# as well. Add a hand-crafted error message here.
+#
+# Use --quiet instead of 2>/dev/null when we upgrade the minimum version
+# of binutils to 2.37, llvm to 13.0.0.
+#
+# Then, the following line will be really simple:
+# done < <(${NM} --quiet ${1})
+(${NM} ${1} 2>/dev/null || { echo "${0}: ${NM} failed" >&2; false; } ) | \
while read value type name
do
# Skip the line if the number of fields is less than 3.
@@ -37,21 +49,7 @@ do
if [[ ${name} == __ksymtab_* ]]; then
export_symbols+=(${name#__ksymtab_})
fi
-
- # If there is no symbol in the object, ${NM} (both GNU nm and llvm-nm)
- # shows 'no symbols' diagnostic (but exits with 0). It is harmless and
- # hidden by '2>/dev/null'. However, it suppresses real error messages
- # as well. Add a hand-crafted error message here.
- #
- # Use --quiet instead of 2>/dev/null when we upgrade the minimum version
- # of binutils to 2.37, llvm to 13.0.0.
- #
- # Then, the following line will be really simple:
- # done < <(${NM} --quiet ${1})
-done < <(${NM} ${1} 2>/dev/null || { echo "${0}: ${NM} failed" >&2; false; } )
-
-# Catch error in the process substitution
-wait $!
+done
for name in "${export_symbols[@]}"
do
--
2.36.1
