From 3a0fb608e64ee4be1deb49a3b68e5090a5f6dcda Mon Sep 17 00:00:00 2001
From: Dominique Belhachemi <domibel@debian.org>
Date: Tue, 30 Sep 2025 13:05:17 -0400
Subject: [PATCH] Lower optimization to -O1 on alpha to fix FTBFS

---
 debian/changelog | 1 +
 debian/rules     | 5 +++++
 2 files changed, 6 insertions(+)

diff --git a/debian/changelog b/debian/changelog
index 684cd17eb..650eb5aae 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -2,6 +2,7 @@ vtk9 (9.5.2+dfsg2-1~exp3) UNRELEASED; urgency=medium
 
   * Team upload
   * Add PPC64 patch
+  * Lower optimization to -O1 on alpha to fix FTBFS
 
  -- Dominique Belhachemi <domibel@debian.org>  Tue, 30 Sep 2025 12:20:57 -0400
 
diff --git a/debian/rules b/debian/rules
index 7f111b13d..761b3d7d5 100755
--- a/debian/rules
+++ b/debian/rules
@@ -25,6 +25,11 @@ else
   extra_flags += -DVTK_SMP_IMPLEMENTATION_TYPE:STRING="OpenMP"
 endif
 
+# Work around FTBFS on Alpha (assembler error "No lda !gpdisp!")
+ifneq (,$(filter $(DEB_HOST_ARCH),alpha))
+  export DEB_CXXFLAGS_MAINT_APPEND += -O1
+endif
+
 %:
 	dh $@ --buildsystem=cmake --builddirectory=$(BUILDDIR)
 
-- 
2.30.2