On Fri, 2018-07-20 at 09:48 +0200, Dirk Gouders wrote: > The kbuild function if_changed should not be called more than once for > a target. > > Because that function writes the command line to a .cmd file for later > tests, multiple calls of it within a target would result in overwrites > of previous values and effectively render the command line test > meaningless, resulting in flip-flop behaviour. > > Add a check for makefiles and kbuild files and produce an error for > targets with multiple calls to if_changed. > > Three examples that now could be detected: > > 98f78525371b55ccd (x86/boot: Refuse to build with data relocations) > 6a8dfe1cac5c591ae (microblaze: support U-BOOT image format) > 684151a75bf25f5ae (sparc32: added U-Boot build target: uImage) > > Reviewed-by: Joe Perches <joe@xxxxxxxxxxx> I didn't review this. I gave you feedback but didn't add a signature. For anything other than "Suggested-by:", please don't add signatures to patches unless the person gives directly gives you one. > Suggested-by: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx> > Signed-off-by: Dirk Gouders <dirk@xxxxxxxxxxx> > --- > v2: rework commit message and regular expression > --- > scripts/checkpatch.pl | 8 ++++++++ > 1 file changed, 8 insertions(+) > > diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl > index 447857ffaf6b..437e98414f74 100755 > --- a/scripts/checkpatch.pl > +++ b/scripts/checkpatch.pl > @@ -2911,6 +2911,14 @@ sub process { > "Use of $flag is deprecated, please use \`$replacement->{$flag} instead.\n" . $herecurr) if ($replacement->{$flag}); > } > > + # Check for multiple calls of if_changed within a target in Makefiles > + if (($realfile =~ /Makefile.*/ || $realfile =~ /Kbuild.*/) && The uses of .* here are superfluous. > + ($prevline =~ /^[ +]\t\s*\$\(call\s+if_changed,/) && > + ($line =~ /^[ +]\t\s*\$\(call\s+if_changed,/)) { > + ERROR("MULTIPLE_IF_CHANGED", > + "Multiple calls of if_changed within a target.\n" . $herecurr); > + } > + > # check for DT compatible documentation > if (defined $root && > (($realfile =~ /\.dtsi?$/ && $line =~ /^\+\s*compatible\s*=\s*\"/) || -- To unsubscribe from this list: send the line "unsubscribe linux-kbuild" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html