diff -r a726281c809f -r 802ab24f67aa make/project.xml
--- a/make/project.xml	Tue Dec 23 10:00:02 2025 +0100
+++ b/make/project.xml	Tue Dec 23 10:14:13 2025 +0100
@@ -94,6 +94,11 @@
         <ldflags>-fsanitize=address</ldflags>
     </dependency>
 
+    <dependency name="ubsan" toolchain="gnuc">
+        <cflags>-fsanitize=undefined</cflags>
+        <ldflags>-fsanitize=undefined</ldflags>
+    </dependency>
+
     <dependency name="no_coverage">
         <test>test -z "$FEATURE_COVERAGE"</test>
     </dependency>
@@ -125,6 +130,10 @@
             <desc>address sanitizer</desc>
             <dependencies>asan</dependencies>
         </feature>
+        <feature name="ubsan">
+            <desc>undefined behavior sanitizer</desc>
+            <dependencies>ubsan</dependencies>
+        </feature>
         <feature name="cxx-tests" default="true">
             <dependencies>cxx</dependencies>
             <desc>the check-cxx makefile target</desc>