diff -Nru lasi-1.1.0/debian/changelog lasi-1.1.0/debian/changelog
--- lasi-1.1.0/debian/changelog	2020-03-24 14:05:21.000000000 +0000
+++ lasi-1.1.0/debian/changelog	2021-10-15 12:20:05.000000000 +0000
@@ -1,3 +1,10 @@
+lasi (1.1.0-2ubuntu3) devel; urgency=medium
+
+  * Fix FTBFS with C++17/GCC-11 (Closes: #984083)
+    + debian/patches/fix-gcc11-throw-ftbfs.patch
+
+ -- Lukas Märdian <slyon@ubuntu.com>  Fri, 15 Oct 2021 14:20:05 +0200
+
 lasi (1.1.0-2ubuntu2) focal; urgency=medium
 
   * No-change rebuild for libgcc-s1 package name change.
diff -Nru lasi-1.1.0/debian/patches/fix-gcc11-throw-ftbfs.patch lasi-1.1.0/debian/patches/fix-gcc11-throw-ftbfs.patch
--- lasi-1.1.0/debian/patches/fix-gcc11-throw-ftbfs.patch	1970-01-01 00:00:00.000000000 +0000
+++ lasi-1.1.0/debian/patches/fix-gcc11-throw-ftbfs.patch	2021-10-15 12:20:05.000000000 +0000
@@ -0,0 +1,22 @@
+Description: Avoid dynamic exception spec, to fix build with C++17 (GCC-11)
+ GCC 11 defaults to C++17 which does not allow dynamic exception
+ specifications anymore. Replace "throw(std::runtime_error)" with
+ "noexcept(false)" as described in https://gcc.gnu.org/gcc-11/porting_to.html
+Author: Lukas Märdian <slyon@ubuntu.com>
+Origin: vendor, Ubuntu
+Bug-Debian: https://bugs.debian.org/984083
+Forwarded: no
+Last-Update: 2021-10-15
+---
+This patch header follows DEP-3: http://dep.debian.net/deps/dep3/
+--- lasi-1.1.0.orig/src/util.h
++++ lasi-1.1.0/src/util.h
+@@ -27,7 +27,7 @@ std::ostream& operator<<(std::ostream&,
+ 
+ /** Converts a freetype return code into an exception.
+  */
+-inline void evalReturnCode(const int errCode, const char* funcName) throw (std::runtime_error) {
++inline void evalReturnCode(const int errCode, const char* funcName) noexcept(false) {
+   if (errCode)
+     throw std::runtime_error(std::string("Error returned from ") + funcName);
+ }
diff -Nru lasi-1.1.0/debian/patches/series lasi-1.1.0/debian/patches/series
--- lasi-1.1.0/debian/patches/series	2014-06-19 11:47:21.000000000 +0000
+++ lasi-1.1.0/debian/patches/series	2021-10-15 12:12:42.000000000 +0000
@@ -1 +1,2 @@
 fix-freetype-ftbfs
+fix-gcc11-throw-ftbfs.patch