diff --git a/src/util/exception_utils.cpp b/src/util/exception_utils.cpp
index 411cc3e23f1..54f1884e4a9 100644
--- a/src/util/exception_utils.cpp
+++ b/src/util/exception_utils.cpp
@@ -87,6 +87,12 @@ std::string analysis_exceptiont::what() const
   return reason;
 }
 
+invalid_source_file_exceptiont::invalid_source_file_exceptiont(
+  std::string reason)
+  : reason(std::move(reason))
+{
+}
+
 std::string invalid_source_file_exceptiont::what() const
 {
   return reason;
diff --git a/src/util/exception_utils.h b/src/util/exception_utils.h
index 0dcb74be6dd..20d9f38a91a 100644
--- a/src/util/exception_utils.h
+++ b/src/util/exception_utils.h
@@ -126,6 +126,7 @@ class analysis_exceptiont : public cprover_exception_baset
 class invalid_source_file_exceptiont : public cprover_exception_baset
 {
 public:
+  explicit invalid_source_file_exceptiont(std::string reason);
   std::string what() const override;
 
 private: