From 41248aad1e9aa103a57d8888a7da9f7cbe8897f3 Mon Sep 17 00:00:00 2001
From: Sunguk Lee <d3m3vilurr@gmail.com>
Date: Sun, 22 Jul 2018 02:52:55 +0900
Subject: [PATCH] Add NEED_ALLOCA macro

since a9438d1f5e, project introduced alloca calls.
but in [BSD manpage][1], this function is machine and compiler dependent.
also if use newlib or glibc, this function requires `alloca.h` unlike bsd
system.

this patch just revert alloca call except MSC case.

[1]: https://www.freebsd.org/cgi/man.cgi?alloca
---
 reedsolomon/rs.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/reedsolomon/rs.c b/reedsolomon/rs.c
index 3a5514f..5ab23ba 100644
--- a/reedsolomon/rs.c
+++ b/reedsolomon/rs.c
@@ -42,6 +42,7 @@
 #include "rs.h"
 
 #ifdef _MSC_VER
+#define NEED_ALLOCA
 #define alloca(x) _alloca(x)
 #endif
 
@@ -225,10 +226,17 @@ static int invert_mat(gf *src, int k) {
     int irow, icol, row, col, i, ix;
 
     int error = 1;
+#ifdef NEED_ALLOCA
     int *indxc = alloca(k*sizeof(int));
     int *indxr = alloca(k*sizeof(int));
     int *ipiv = alloca(k*sizeof(int));
     gf *id_row = alloca(k*sizeof(gf));
+#else
+    int indxc[k];
+    int indxr[k];
+    int ipiv[k];
+    gf id_row[k];
+#endif
 
     memset(id_row, 0, k*sizeof(gf));
     /*