diff -Nru ktx-1.45/debian/changelog ktx-1.45/debian/changelog
--- ktx-1.45/debian/changelog	2025-04-10 17:43:44.000000000 +0530
+++ ktx-1.45/debian/changelog	2026-05-23 17:43:50.000000000 +0530
@@ -1,3 +1,17 @@
+ktx (1.45-1.1) unstable; urgency=medium
+
+  * Non-maintainer upload.
+  * Fix FTBFS with GCC 15 / C23 (Closes: #1114163):
+    include/q_shared.h defines 'typedef enum { false, true } qbool;'.
+    Under C23 'false' and 'true' are reserved keywords and cannot be
+    used as enumeration constants. Backport upstream commit
+    4d04c6e53ba305222559dd47c4dfb50f959cd696 by ciscon (PR #428,
+    merged 2025-10-19) which adds -std=gnu17 to the non-MSVC compile
+    options in CMakeLists.txt so the legacy boolean enum continues to
+    compile.
+
+ -- Azeez Syed <azeezalishah@gmail.com>  Sat, 23 May 2026 18:00:00 +0530
+
 ktx (1.45-1) unstable; urgency=high
 
   * New upstream version 1.45
diff -Nru ktx-1.45/debian/patches/0002-fix-ftbfs-gcc15-std-gnu17.patch ktx-1.45/debian/patches/0002-fix-ftbfs-gcc15-std-gnu17.patch
--- ktx-1.45/debian/patches/0002-fix-ftbfs-gcc15-std-gnu17.patch	1970-01-01 05:30:00.000000000 +0530
+++ ktx-1.45/debian/patches/0002-fix-ftbfs-gcc15-std-gnu17.patch	2026-05-23 17:41:56.000000000 +0530
@@ -0,0 +1,32 @@
+Description: Fix FTBFS with GCC 15 / C23: build with -std=gnu17
+ include/q_shared.h:146 defines a legacy pre-C99 boolean type via
+ 'typedef enum { false, true } qbool;'. Under C23 (the GCC 15 default)
+ 'false' and 'true' are reserved keywords and cannot be used as
+ enumeration constants, so the build fails for every translation unit
+ that includes q_shared.h:
+ .
+   q_shared.h:146:9: error: cannot use keyword 'false' as enumeration
+                            constant
+   note: 'false' is a keyword with '-std=c23' onwards
+ .
+ Upstream's chosen fix (PR #428, commit 4d04c6e by ciscon, merged
+ 2025-10-19) is to build with -std=gnu17 rather than rewriting the
+ boolean type across the codebase. Add -std=gnu17 to the non-MSVC
+ compile options in CMakeLists.txt to match upstream.
+Author: Azeez Syed <azeezalishah@gmail.com>
+Origin: upstream, https://github.com/QW-Group/ktx/commit/4d04c6e53ba305222559dd47c4dfb50f959cd696
+Bug-Debian: https://bugs.debian.org/1114163
+Bug: https://github.com/QW-Group/ktx/issues/422
+Forwarded: not-needed
+Last-Update: 2026-05-23
+--- a/CMakeLists.txt
++++ b/CMakeLists.txt
+@@ -159,7 +159,7 @@ if (CMAKE_C_COMPILER_ID STREQUAL "MSVC")
+ 	# 4459 - shadowing globals, broadly used
+ 	target_compile_options(${PROJECT_NAME} PRIVATE /W4 /wd4100 /wd4210 /wd4456 /wd4459)
+ else()
+-	target_compile_options(${PROJECT_NAME} PRIVATE -Wall)
++	target_compile_options(${PROJECT_NAME} PRIVATE -Wall -std=gnu17)
+ 
+ 	check_c_compiler_flag("-Wstrict-prototypes" HAS_CFLAG_STRICT_PROTOTYPES)
+ 	if (HAS_CFLAG_STRICT_PROTOTYPES)
diff -Nru ktx-1.45/debian/patches/series ktx-1.45/debian/patches/series
--- ktx-1.45/debian/patches/series	2022-11-21 02:27:38.000000000 +0530
+++ ktx-1.45/debian/patches/series	2026-05-23 17:39:39.000000000 +0530
@@ -1 +1,2 @@
 0001-remove-q3lcc.patch
+0002-fix-ftbfs-gcc15-std-gnu17.patch