From: Eric Wong <e@80x24.org>
Date: Fri, 13 Oct 2023 06:12:29 +0000 (+0000)
Subject: xap_helper_cxx: allow sharing XDG_CACHE_HOME across ABIs
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=c24f57d19f6536d750c8571cda015d9fd57d3a58;p=thirdparty%2Fpublic-inbox.git

xap_helper_cxx: allow sharing XDG_CACHE_HOME across ABIs

For users sharing home directories (or just XDG_CACHE_HOME)
across hosts of different architectures, we must use a compiler
and architecture-specific destination directory for storing the
binary result.  Even on the same OS and architecture, different
C++ compilers may have different ABIs, so we must account for
that.
---

diff --git a/lib/PublicInbox/XapHelperCxx.pm b/lib/PublicInbox/XapHelperCxx.pm
index 5157fb35c..90ddd80fd 100644
--- a/lib/PublicInbox/XapHelperCxx.pm
+++ b/lib/PublicInbox/XapHelperCxx.pm
@@ -7,11 +7,15 @@
 # The resulting executable is not linked to Perl in any way.
 package PublicInbox::XapHelperCxx;
 use v5.12;
-use PublicInbox::Spawn qw(popen_rd);
+use PublicInbox::Spawn qw(popen_rd which);
 use PublicInbox::Search;
 use Fcntl qw(SEEK_SET);
-my $dir = ($ENV{PERL_INLINE_DIRECTORY} //
-	die('BUG: PERL_INLINE_DIRECTORY unset')) . '/cxx';
+use Config;
+my $cxx = which($ENV{CXX} // 'c++');
+my $dir = substr("$cxx-$Config{archname}", 1); # drop leading '/'
+$dir =~ tr!/!-!;
+$ENV{PERL_INLINE_DIRECTORY} // die('BUG: PERL_INLINE_DIRECTORY unset');
+substr($dir, 0, 0) = "$ENV{PERL_INLINE_DIRECTORY}/";
 my $bin = "$dir/xap_helper";
 my ($srcpfx) = (__FILE__ =~ m!\A(.+/)[^/]+\z!);
 my @srcs = map { $srcpfx.$_ } qw(xap_helper.h);
@@ -85,7 +89,6 @@ sub build () {
 	$^O eq 'netbsd' and $fl =~ s/(\A|[ \t])\-L([^ \t]+)([ \t]|\z)/
 				"$1-L$2 -Wl,-rpath=$2$3"/egsx;
 
-	my $cxx = $ENV{CXX} // 'c++';
 	my $cmd = "$cxx $src $fl $xflags -o $tmp/$prog";
 	system($cmd) and die "$cmd failed: \$?=$?";
 	open $fh, '>', "$tmp/XFLAGS";