From 943bf87b3a3ca1b65a3d789466b7146ab9456ada Mon Sep 17 00:00:00 2001
From: flipflip <flipflip@fixposition.com>
Date: Wed, 5 Aug 2026 12:57:18 +0200
Subject: [PATCH 1/4] also do clang CI on Lyrical/Ubuntu26

---
 docker/ci.sh                       | 4 ++--
 docker/scripts/install_apt_base.sh | 1 +
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/docker/ci.sh b/docker/ci.sh
index 28e3238..d88c7b6 100755
--- a/docker/ci.sh
+++ b/docker/ci.sh
@@ -555,9 +555,9 @@ do_step build_projs_release_noros_mindeps      || true # continue
 
 do_step build_examples                 || true # continue
 
-# Some minimal checks with clang
+# Some minimal checks with clang on the reference system (Trixie) and a more recent Ubuntu 26 (= ROS2 Lyrical)
 echo "===== clang ====="
-if [ "${FPSDK_IMAGE%-*}" = "trixie" ]; then
+if [ "${FPSDK_IMAGE%-*}" = "trixie" -o "${FPSDK_IMAGE%-*}" = "lyrical" ]; then
     do_step build_toplevel_release_clang  || true # continue
     do_step build_toplevel_debug_clang    || true # continue
 fi
diff --git a/docker/scripts/install_apt_base.sh b/docker/scripts/install_apt_base.sh
index 75fe8a6..a6e255b 100755
--- a/docker/scripts/install_apt_base.sh
+++ b/docker/scripts/install_apt_base.sh
@@ -44,6 +44,7 @@ packages=$(awk -v filt=${FPSDK_IMAGE%-*} '$1 ~ filt { print $2 }' <<EOF
     ..............jazzy.lyrical.trixie      libproj25
     ..............jazzy.lyrical.trixie      libproj-dev
     noetic.humble.jazzy.lyrical.trixie      libssl-dev
+    ....................lyrical.......      libstdc++-16-dev
     noetic.humble.jazzy.lyrical.trixie      libsqlite3-dev
     noetic.humble.jazzy.lyrical.trixie      libtiff-dev
     noetic.humble.jazzy.lyrical.trixie      libva-dev                         # automatically installs va-driver-all?

From afaa7e5a85736c9b42b385505cb359723e0ac2f5 Mon Sep 17 00:00:00 2001
From: flipflip <flipflip@fixposition.com>
Date: Wed, 5 Aug 2026 13:03:57 +0200
Subject: [PATCH 2/4] explicitly set c and c++ compiler

---
 Makefile     | 10 +++++++++-
 docker/ci.sh |  4 ++--
 2 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/Makefile b/Makefile
index ff62fe3..c97dd61 100644
--- a/Makefile
+++ b/Makefile
@@ -12,6 +12,8 @@ BUILD_TESTING  =
 VERBOSE        = 0
 USE_PROJ       =
 USE_FFMPEG     =
+C_COMPILER     =
+CXX_COMPILER   =
 
 # User vars
 -include config.mk
@@ -28,7 +30,7 @@ else ifeq ($(ROS_VERSION),2)
 endif
 
 # A unique ID for this exact config we're using
-configuid=$(shell echo "$(BUILD_TYPE) $(INSTALL_PREFIX) $(BUILD_TESTING) $(USE_PROJ) $(USE_FFMPEG) $(FPSDK_VERSION_STRING) $(CC) $(CXX) $$(uname -a)" | md5sum | cut -d " " -f1)
+configuid=$(shell echo "$(BUILD_TYPE) $(INSTALL_PREFIX) $(BUILD_TESTING) $(USE_PROJ) $(USE_FFMPEG) $(FPSDK_VERSION_STRING) $(C_COMPILER) $(CXX_COMPILER) $$(uname -a)" | md5sum | cut -d " " -f1)
 
 .PHONY: help
 help:
@@ -139,6 +141,12 @@ endif
 ifneq ($(FPSDK_VERSION_STRING),)
   CMAKE_ARGS += -DVERSION_STRING=$(FPSDK_VERSION_STRING)
 endif
+ifneq ($(C_COMPILER),)
+  CMAKE_ARGS += -DCMAKE_C_COMPILER=$(C_COMPILER)
+endif
+ifneq ($(CXXCOMPILER),)
+  CMAKE_ARGS += -DCMAKE_CXXCOMPILER=$(CXXCOMPILER)
+endif
 
 ifeq ($(BUILD_TYPE),Release)
   CMAKE_ARGS_INSTALL += --strip
diff --git a/docker/ci.sh b/docker/ci.sh
index d88c7b6..a1459fd 100755
--- a/docker/ci.sh
+++ b/docker/ci.sh
@@ -207,7 +207,7 @@ function build_toplevel_release_clang
     cd ${FPSDK_SRC_DIR}
     rm -rf build/${buildname}
     make install \
-        CC=clang CXX=clang++ \
+        C_COMPILER=clang CXX_COMPILER=clang++ \
         INSTALL_PREFIX=install/${buildname} \
         BUILD_TYPE=Release \
         BUILD_DIR=build/${buildname} || return 1
@@ -222,7 +222,7 @@ function build_toplevel_debug_clang
     cd ${FPSDK_SRC_DIR}
     rm -rf build/${buildname}
     make install \
-        CC=clang CXX=clang++ \
+        C_COMPILER=clang CXX_COMPILER=clang++ \
         INSTALL_PREFIX=install/${buildname} \
         BUILD_TYPE=Debug \
         BUILD_DIR=build/${buildname} || return 1

From b0ca5f7f20233a1e08f047fee67384863ee4a388 Mon Sep 17 00:00:00 2001
From: flipflip <flipflip@fixposition.com>
Date: Wed, 5 Aug 2026 13:08:06 +0200
Subject: [PATCH 3/4] docu

---
 docker/scripts/install_apt_base.sh | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docker/scripts/install_apt_base.sh b/docker/scripts/install_apt_base.sh
index a6e255b..df54b96 100755
--- a/docker/scripts/install_apt_base.sh
+++ b/docker/scripts/install_apt_base.sh
@@ -44,7 +44,7 @@ packages=$(awk -v filt=${FPSDK_IMAGE%-*} '$1 ~ filt { print $2 }' <<EOF
     ..............jazzy.lyrical.trixie      libproj25
     ..............jazzy.lyrical.trixie      libproj-dev
     noetic.humble.jazzy.lyrical.trixie      libssl-dev
-    ....................lyrical.......      libstdc++-16-dev
+    ....................lyrical.......      libstdc++-16-dev                  # For clang
     noetic.humble.jazzy.lyrical.trixie      libsqlite3-dev
     noetic.humble.jazzy.lyrical.trixie      libtiff-dev
     noetic.humble.jazzy.lyrical.trixie      libva-dev                         # automatically installs va-driver-all?

From 8cf9e9baf5a323e7028ede1201a393d1ac28878b Mon Sep 17 00:00:00 2001
From: flipflip <flipflip@fixposition.com>
Date: Wed, 5 Aug 2026 13:32:42 +0200
Subject: [PATCH 4/4] fix

---
 Makefile | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/Makefile b/Makefile
index c97dd61..0ac1b8c 100644
--- a/Makefile
+++ b/Makefile
@@ -144,8 +144,8 @@ endif
 ifneq ($(C_COMPILER),)
   CMAKE_ARGS += -DCMAKE_C_COMPILER=$(C_COMPILER)
 endif
-ifneq ($(CXXCOMPILER),)
-  CMAKE_ARGS += -DCMAKE_CXXCOMPILER=$(CXXCOMPILER)
+ifneq ($(CXX_COMPILER),)
+  CMAKE_ARGS += -DCMAKE_CXX_COMPILER=$(CXX_COMPILER)
 endif
 
 ifeq ($(BUILD_TYPE),Release)
@@ -196,7 +196,7 @@ cmake: $(BUILD_DIR)/.make-cmake
 deps_cmake := Makefile $(wildcard config.mk) $(wildcard $(sort $(wildcard CMakeLists.txt */CMakeLists.txt */cmake/*)))
 
 $(BUILD_DIR)/.make-cmake: $(deps_cmake) $(BUILD_DIR)/.make-configuid-$(configuid)
-	@echo "$(HLW)***** Configure ($(BUILD_TYPE)) *****$(HLO)"
+	@echo "$(HLW)***** Configure ($(CMAKE_ARGS)) *****$(HLO)"
 	$(V)$(CMAKE) -B $(BUILD_DIR) $(CMAKE_ARGS)
 	$(V)$(TOUCH) $@