From 1dedd0ebca5fc19c7f08d244ed72a1abc57699ae Mon Sep 17 00:00:00 2001
From: Jan Nieuwenhuizen <janneke@gnu.org>
Date: Sun, 20 May 2018 08:33:06 +0200
Subject: [PATCH] mescc: Fix itoa.

* lib/libc.c (itoa): Use function-static buffer.  Increase to 12 to
  handle INT_MIN.
  (itoab): Likewise.
---
 lib/libc.c               | 46 +++++++++++++++++++---------------------
 scaffold/tests/52-itoa.c | 13 ++++++++----
 2 files changed, 31 insertions(+), 28 deletions(-)

diff --git a/lib/libc.c b/lib/libc.c
index 1427ba2d..40be8a44 100644
--- a/lib/libc.c
+++ b/lib/libc.c
@@ -91,28 +91,26 @@ atoi (char const *s)
   return abtoi (&p, 0);
 }
 
-char itoa_buf[10];
-
 char const*
 itoa (int x)
 {
-  //static char itoa_buf[10];
-  //char *p = buf+9;
-  char *p = itoa_buf;
-  p += 9;
+  static char itoa_buf[12];
+  char *p = itoa_buf + 11;
   *p-- = 0;
 
-  //int sign = x < 0; // FIXME
   int sign = 0;
-  if (x < 0) sign = 1;
-  if (sign)
-    x = -x;
+  unsigned u = x;
+  if (x < 0)
+    {
+      sign = 1;
+      u = -x;
+    }
 
   do
      {
-       *p-- = '0' + (x % 10);
-       x = x / 10;
-     } while (x);
+       *p-- = '0' + (u % 10);
+       u = u / 10;
+     } while (u);
 
   if (sign && *(p + 1) != '0')
     *p-- = '-';
@@ -123,24 +121,24 @@ itoa (int x)
 char const*
 itoab (int x, int base)
 {
-  //static char itoa_buf[10];
-  //char *p = buf+9;
-  char *p = itoa_buf;
-  p += 9;
+  static char itoa_buf[12];
+  char *p = itoa_buf + 11;
   *p-- = 0;
 
-  //int sign = x < 0; // FIXME
   int sign = 0;
-  if (x < 0) sign = 1;
-  if (sign)
-    x = -x;
+  unsigned u = x;
+  if (x < 0)
+    {
+      sign = 1;
+      u = -x;
+    }
 
   do
      {
-       int i = x % base;
+       int i = u % base;
        *p-- = i > 9 ? 'a' + i - 10 : '0' + i;
-       x = x / base;
-     } while (x);
+       x = u / base;
+     } while (u);
 
   if (sign && *(p + 1) != '0')
     *p-- = '-';
diff --git a/scaffold/tests/52-itoa.c b/scaffold/tests/52-itoa.c
index 634b2ab1..e2630038 100644
--- a/scaffold/tests/52-itoa.c
+++ b/scaffold/tests/52-itoa.c
@@ -30,16 +30,21 @@ test ()
 
   puts ("\n");
   puts ("t: itoa (33) == \"33\"\n");
-  if (strcmp (itoa (33), "33")) return 1;
+  if (strcmp (itoa (33), "33"))
+    return 1;
 
   puts ("strcmp (itoa (-1), \"-1\")\n");
-  if (strcmp (itoa (-1), "-1")) return 1;
+  puts (itoa (-1));
+  if (strcmp (itoa (-1), "-1"))
+    return 2;
 
   puts ("strcmp (itoa (0), \"0\")\n");
-  if (strcmp (itoa (0), "0")) return 1;
+  if (strcmp (itoa (0), "0"))
+    return 3;
 
   puts ("strcmp (itoa (1), \"1\")\n");
-  if (strcmp (itoa (1), "1")) return 1;
+  if (strcmp (itoa (1), "1"))
+    return 4;
 
   return 0;
 }