Merge tag 'kbuild-v5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild updates from Masahiro Yamada:

 - Increase the -falign-functions alignment for the debug option.

 - Remove ugly libelf checks from the top Makefile.

 - Make the silent build (-s) more silent.

 - Re-compile the kernel if KBUILD_BUILD_TIMESTAMP is specified.

 - Various script cleanups

* tag 'kbuild-v5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (27 commits)
  scripts: add generic syscallnr.sh
  scripts: check duplicated syscall number in syscall table
  sparc: syscalls: use pattern rules to generate syscall headers
  parisc: syscalls: use pattern rules to generate syscall headers
  nds32: add arch/nds32/boot/.gitignore
  kbuild: mkcompile_h: consider timestamp if KBUILD_BUILD_TIMESTAMP is set
  kbuild: modpost: Explicitly warn about unprototyped symbols
  kbuild: remove trailing slashes from $(KBUILD_EXTMOD)
  kconfig.h: explain IS_MODULE(), IS_ENABLED()
  kconfig: constify long_opts
  scripts/setlocalversion: simplify the short version part
  scripts/setlocalversion: factor out 12-chars hash construction
  scripts/setlocalversion: add more comments to -dirty flag detection
  scripts/setlocalversion: remove workaround for old make-kpkg
  scripts/setlocalversion: remove mercurial, svn and git-svn supports
  kbuild: clean up ${quiet} checks in shell scripts
  kbuild: sink stdout from cmd for silent build
  init: use $(call cmd,) for generating include/generated/compile.h
  kbuild: merge scripts/mkmakefile to top Makefile
  sh: move core-y in arch/sh/Makefile to arch/sh/Kbuild
  ...

1 files changed, 12 insertions, 6 deletions

diff --git a/scripts/mkcompile_h b/scripts/mkcompile_h
index 4ae735039daf..6a2a04d92f42 100755
--- a/scripts/mkcompile_h
+++ b/scripts/mkcompile_h
@@ -9,8 +9,6 @@ PREEMPT_RT=$5
 CC_VERSION="$6"
 LD=$7
 
-vecho() { [ "${quiet}" = "silent_" ] || echo "$@" ; }
-
 # Do not expand names
 set -f
 
@@ -70,19 +68,27 @@ UTS_VERSION="$(echo $UTS_VERSION $CONFIG_FLAGS $TIMESTAMP | cut -b -$UTS_LEN)"
 # Only replace the real compile.h if the new one is different,
 # in order to preserve the timestamp and avoid unnecessary
 # recompilations.
-# We don't consider the file changed if only the date/time changed.
+# We don't consider the file changed if only the date/time changed,
+# unless KBUILD_BUILD_TIMESTAMP was explicitly set (e.g. for
+# reproducible builds with that value referring to a commit timestamp).
 # A kernel config change will increase the generation number, thus
 # causing compile.h to be updated (including date/time) due to the
 # changed comment in the
 # first line.
 
+if [ -z "$KBUILD_BUILD_TIMESTAMP" ]; then
+   IGNORE_PATTERN="UTS_VERSION"
+else
+   IGNORE_PATTERN="NOT_A_PATTERN_TO_BE_MATCHED"
+fi
+
 if [ -r $TARGET ] && \
-      grep -v 'UTS_VERSION' $TARGET > .tmpver.1 && \
-      grep -v 'UTS_VERSION' .tmpcompile > .tmpver.2 && \
+      grep -v $IGNORE_PATTERN $TARGET > .tmpver.1 && \
+      grep -v $IGNORE_PATTERN .tmpcompile > .tmpver.2 && \
       cmp -s .tmpver.1 .tmpver.2; then
    rm -f .tmpcompile
 else
-   vecho "  UPD     $TARGET"
+   echo "  UPD     $TARGET"
    mv -f .tmpcompile $TARGET
 fi
 rm -f .tmpver.1 .tmpver.2