[libpng16] Use minus signs, not hyphens, in "--i".

1 files changed, 1 insertions, 1 deletions

diff --git a/libpng.3 b/libpng.3
index 18e21a0e1..064bf4c74 100644
--- a/libpng.3
+++ b/libpng.3
@@ -5706,7 +5706,7 @@ C binary operator and after "for" or "while", and before
 being cast, nor do we put one between a function name and the
 left parenthesis that follows it:
 
-    for (i = 2; i > 0; --i)
+    for (i = 2; i > 0; \-\-i)
        y[i] = a(x) + (int)b;
 
 We prefer #ifdef and #ifndef to #if defined() and #if !defined()