backport https://github.com/audacious-media-player/audacious/commit/6ffe0b6.patch
https://bugs.gentoo.org/972499
audcore: Prevent undefined behavior for integer conversions.
--- a/src/libaudcore/audstrings.cc
+++ b/src/libaudcore/audstrings.cc
@@ -1121,8 +1121,10 @@ EXPORT double str_to_double(const char * string)
 
 EXPORT void str_insert_int(StringBuf & string, int pos, int val)
 {
+    unsigned absval = val;
     bool neg = (val < 0);
-    unsigned absval = neg ? -val : val;
+    if (neg)
+        absval = -absval;
 
     int digits = digits_for(absval);
     int len = (neg ? 1 : 0) + digits;