pkg/cover: improve prefix computation

When the prefix becomes the empty string during the computation,
stop computing it, since the empty string is the result.

1 files changed, 3 insertions, 1 deletions

diff --git a/pkg/cover/report.go b/pkg/cover/report.go
index a4878dba4..0b2600f22 100644
--- a/pkg/cover/report.go
+++ b/pkg/cover/report.go
@@ -239,8 +239,10 @@ func (rg *ReportGenerator) symbolize(pcs []uint64) ([]symbolizer.Frame, string,
 				}
 			}
 			prefix = prefix[:i]
+			if prefix == "" {
+				break
+			}
 		}
-
 	}
 	return frames, prefix, nil
 }