Bug#1126389: libalgorithm-svm-perl FTCBFS: uses the build architecture C++ compiler

[Helmut Grohne]

Source: libalgorithm-svm-perl
Version: 0.13-4
Tags: patch
User: debian-cross at lists.debian.org
Usertags: ftcbfs

libalgorithm-svm-perl fails to cross build from source, because the
upstream build system wants to use a C++ compiler with Perl's
ExtUtils:MakeMaker and thus overrides the chosen C compiler. In doing
so, it forces a build architecture compiler where a host architecture on
would be needed. Since Perl does not usually use C++, the host
architecture C++ compiler is not something we can query from Perl. I
propose honouring the CXX environment variable and supplying it from
debian/rules instead. Once doing so, libalgorithm-svm-perl cross builds
successfully. I'm attaching a patch for your convenience.

Helmut
-------------- next part --------------
diff -Nru libalgorithm-svm-perl-0.13/debian/changelog libalgorithm-svm-perl-0.13/debian/changelog
--- libalgorithm-svm-perl-0.13/debian/changelog	2024-03-04 14:32:15.000000000 +0100
+++ libalgorithm-svm-perl-0.13/debian/changelog	2026-01-24 13:10:25.000000000 +0100
@@ -1,3 +1,10 @@
+libalgorithm-svm-perl (0.13-4.1) UNRELEASED; urgency=medium
+
+  * Non-maintainer upload.
+  * Fix FTCBFS: Use the host compiler. (Closes: #-1)
+
+ -- Helmut Grohne <helmut at subdivi.de>  Sat, 24 Jan 2026 13:10:25 +0100
+
 libalgorithm-svm-perl (0.13-4) unstable; urgency=medium
 
   * Team upload.
diff -Nru libalgorithm-svm-perl-0.13/debian/patches/cross.patch libalgorithm-svm-perl-0.13/debian/patches/cross.patch
--- libalgorithm-svm-perl-0.13/debian/patches/cross.patch	1970-01-01 01:00:00.000000000 +0100
+++ libalgorithm-svm-perl-0.13/debian/patches/cross.patch	2026-01-24 13:10:25.000000000 +0100
@@ -0,0 +1,11 @@
+--- libalgorithm-svm-perl-0.13.orig/Makefile.PL
++++ libalgorithm-svm-perl-0.13/Makefile.PL
+@@ -1,7 +1,7 @@
+ use ExtUtils::MakeMaker;
+ use Config;
+ 
+-$CC = 'g++';
++$CC = $ENV{'CXX'} // 'g++';
+ 
+ %args = ('CCFLAGS' => "-Wall $Config{ccflags}");
+ 
diff -Nru libalgorithm-svm-perl-0.13/debian/patches/series libalgorithm-svm-perl-0.13/debian/patches/series
--- libalgorithm-svm-perl-0.13/debian/patches/series	2024-03-04 14:32:15.000000000 +0100
+++ libalgorithm-svm-perl-0.13/debian/patches/series	2026-01-24 13:08:45.000000000 +0100
@@ -3,3 +3,4 @@
 do-not-link-to-libm.patch
 spelling.patch
 ccflags.patch
+cross.patch
diff -Nru libalgorithm-svm-perl-0.13/debian/rules libalgorithm-svm-perl-0.13/debian/rules
--- libalgorithm-svm-perl-0.13/debian/rules	2024-03-04 14:32:15.000000000 +0100
+++ libalgorithm-svm-perl-0.13/debian/rules	2026-01-24 13:10:25.000000000 +0100
@@ -1,6 +1,8 @@
 #!/usr/bin/make -f
 
 export DEB_BUILD_MAINT_OPTIONS = hardening=+all
+DPKG_EXPORT_BUILDTOOLS := 1
+include /usr/share/dpkg/buildtools.mk
 
 %:
 	dh $@