Commit b18b851b authored by Nathan Chancellor's avatar Nathan Chancellor Committed by Steven Rostedt (VMware)
Browse files

scripts/recordmcount.pl: Remove check_objcopy() and $can_use_local 

When building ARCH=riscv allmodconfig with llvm-objcopy, the objcopy
version warning from this script appears:

WARNING: could not find objcopy version or version is less than 2.17.
        Local function references are disabled.

The check_objcopy() function in scripts/recordmcount.pl is set up to
parse GNU objcopy's version string, not llvm-objcopy's, which triggers
the warning.

Commit 799c4341 ("kbuild: thin archives make default for all archs")
made binutils 2.20 mandatory and commit ba64beb1 ("kbuild: check the
minimum assembler version in Kconfig") enforces this at configuration
time so just remove check_objcopy() and $can_use_local instead, assuming
--globalize-symbol is always available.

llvm-objcopy has supported --globalize-symbol since LLVM 7.0.0 in 2018
and the minimum version for building the kernel with LLVM is 10.0.1 so
there is no issue introduced:

Link: https://github.com/llvm/llvm-project/commit/ee5be798dae30d5f9414b01f76ff807edbc881aa
Link: https://lkml.kernel.org/r/20210802210307.3202472-1-nathan@kernel.org



Reviewed-by: default avatarNick Desaulniers <ndesaulniers@google.com>
Signed-off-by: default avatarNathan Chancellor <nathan@kernel.org>
Signed-off-by: default avatarSteven Rostedt (VMware) <rostedt@goodmis.org>
parent a9d10ca4

Makefile

+0 −1
Original line number Diff line number Diff line
@@ -546,7 +546,6 @@ export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn \ 
PHONY += scripts_basic

scripts_basic:

	$(Q)$(MAKE) $(build)=scripts/basic

	$(Q)rm -f .tmp_quiet_recordmcount



PHONY += outputmakefile

ifdef building_out_of_srctree

scripts/recordmcount.pl

+0 −40
Original line number Diff line number Diff line
@@ -173,39 +173,6 @@ my $mcount_regex; # Find the call site to mcount (return offset) 
my $mcount_adjust;	# Address adjustment to mcount offset

my $alignment;		# The .align value to use for $mcount_section

my $section_type;	# Section header plus possible alignment command

my $can_use_local = 0; 	# If we can use local function references



# Shut up recordmcount if user has older objcopy

my $quiet_recordmcount = ".tmp_quiet_recordmcount";

my $print_warning = 1;

$print_warning = 0 if ( -f $quiet_recordmcount);



##

# check_objcopy - whether objcopy supports --globalize-symbols

#

#  --globalize-symbols came out in 2.17, we must test the version

#  of objcopy, and if it is less than 2.17, then we can not

#  record local functions.

sub check_objcopy

{

    open (IN, "$objcopy --version |") or die "error running $objcopy";

    while (<IN>) {

	if (/objcopy.*\s(\d+)\.(\d+)/) {

	    $can_use_local = 1 if ($1 > 2 || ($1 == 2 && $2 >= 17));

	    last;

	}

    }

    close (IN);



    if (!$can_use_local && $print_warning) {

	print STDERR "WARNING: could not find objcopy version or version " .

	    "is less than 2.17.\n" .

	    "\tLocal function references are disabled.\n";

	open (QUIET, ">$quiet_recordmcount");

	printf QUIET "Disables the warning from recordmcount.pl\n";

	close QUIET;

    }

}



if ($arch =~ /(x86(_64)?)|(i386)/) {

    if ($bits == 64) {
@@ -434,8 +401,6 @@ if ($filename =~ m,^(.*)(\.\S),) { 
my $mcount_s = $dirname . "/.tmp_mc_" . $prefix . ".s";

my $mcount_o = $dirname . "/.tmp_mc_" . $prefix . ".o";



check_objcopy();



#

# Step 1: find all the local (static functions) and weak symbols.

#         't' is local, 'w/W' is weak
@@ -473,11 +438,6 @@ sub update_funcs 


    # is this function static? If so, note this fact.

    if (defined $locals{$ref_func}) {



	# only use locals if objcopy supports globalize-symbols

	if (!$can_use_local) {

	    return;

	}

	$convert{$ref_func} = 1;

    }