libutil: Change return value of addTrace to void

The return value of BaseError::addTrace(...) is never used and
error-prone as subclasses calling it will return a BaseError instead of
the subclass.
This commit changes its return value to be void.

1 files changed, 3 insertions, 3 deletions

diff --git a/src/libutil/error.hh b/src/libutil/error.hh
index 93b789f0b..6a757f9ad 100644
--- a/src/libutil/error.hh
+++ b/src/libutil/error.hh
@@ -175,12 +175,12 @@ public:
     const ErrorInfo & info() const { calcWhat(); return err; }
 
     template<typename... Args>
-    BaseError & addTrace(std::optional<ErrPos> e, const std::string & fs, const Args & ... args)
+    void addTrace(std::optional<ErrPos> e, const std::string & fs, const Args & ... args)
     {
-        return addTrace(e, hintfmt(fs, args...));
+        addTrace(e, hintfmt(fs, args...));
     }
 
-    BaseError & addTrace(std::optional<ErrPos> e, hintformat hint);
+    void addTrace(std::optional<ErrPos> e, hintformat hint);
 
     bool hasTrace() const { return !err.traces.empty(); }
 };