From ad0245bb967b90866663cd8e5d74844031a17cea Mon Sep 17 00:00:00 2001
From: Vadim Zeitlin <vadim@zeitlins.org>
Date: Sat, 2 May 2020 20:29:26 +0200
Subject: [PATCH] Avoid -Wundef for MIPS and PPC symbols too

This is similar to d532334ef (Avoid -Wundef warnings when building
libpng, 2017-11-13), but for the similar symbols used under the other
architectures: always define them, even if just as 0, to avoid gcc
warnings when comparing them with 0 later.
---
 pngpriv.h | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/pngpriv.h b/pngpriv.h
index c07750c20..a8e78e4cc 100644
--- a/pngpriv.h
+++ b/pngpriv.h
@@ -265,11 +265,15 @@
 #  ifndef PNG_MIPS_MSA_IMPLEMENTATION
 #     define PNG_MIPS_MSA_IMPLEMENTATION 1
 #  endif
+#else
+#  define PNG_MIPS_MSA_IMPLEMENTATION 0
 #endif /* PNG_MIPS_MSA_OPT > 0 */
 
 #if PNG_POWERPC_VSX_OPT > 0
 #  define PNG_FILTER_OPTIMIZATIONS png_init_filter_functions_vsx
 #  define PNG_POWERPC_VSX_IMPLEMENTATION 1
+#else
+#  define PNG_POWERPC_VSX_IMPLEMENTATION 0
 #endif