dpkg-buildflags: Add support for new future feature area

This new area includes an lfs feature, to be used instead of the
getconf(1) interfaces which cannot support cross-building.

2 files changed, 18 insertions, 3 deletions

diff --git a/scripts/Dpkg/BuildFlags.pm b/scripts/Dpkg/BuildFlags.pm
index b97e5c779..0533b12b5 100644
--- a/scripts/Dpkg/BuildFlags.pm
+++ b/scripts/Dpkg/BuildFlags.pm
@@ -237,7 +237,7 @@ sub set {
 
 Update the boolean state of whether a specific feature within a known
 feature area has been enabled. The only currently known feature areas
-are "qa", "sanitize", "hardening" and "reproducible".
+are "future", "qa", "sanitize", "hardening" and "reproducible".
 
 =cut
 
@@ -409,8 +409,8 @@ sub is_maintainer_modified {
 =item $bf->has_features($area)
 
 Returns true if the given area of features is known, and false otherwise.
-The only currently recognized feature areas are "qa", "sanitize", "hardening"
-and "reproducible".
+The only currently recognized feature areas are "future", "qa", "sanitize",
+"hardening" and "reproducible".
 
 =cut
 
diff --git a/scripts/Dpkg/Vendor/Debian.pm b/scripts/Dpkg/Vendor/Debian.pm
index 4b5436ee1..e0fd01113 100644
--- a/scripts/Dpkg/Vendor/Debian.pm
+++ b/scripts/Dpkg/Vendor/Debian.pm
@@ -103,6 +103,9 @@ sub _add_build_flags {
 
     # Default feature states.
     my %use_feature = (
+        future => {
+            lfs => 0,
+        },
         qa => {
             bug => 0,
             canary => 0,
@@ -153,6 +156,18 @@ sub _add_build_flags {
         ($abi, $os, $cpu) = ('', '', '');
     }
 
+    ## Area: future
+
+    if ($use_feature{future}{lfs}) {
+        my ($abi_bits, $abi_endian) = Dpkg::Arch::debarch_to_abiattrs($arch);
+        my $cpu_bits = Dpkg::Arch::debarch_to_cpubits($arch);
+
+        if ($abi_bits == 32 and $cpu_bits == 32) {
+            $flags->append('CPPFLAGS',
+                           '-D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64');
+        }
+    }
+
     ## Area: qa
 
     # Warnings that detect actual bugs.