portability: beware of max () with MSVC

Reported by Maarten De Braekeleer.
https://lists.gnu.org/r/bison-patches/2020-07/msg00080.html

We don't want to use gnulib's min and max macros, since we use
function calls in min/max arguments.

* src/location.c (max_int, min_int): Move to...
* src/system.h: here.
* src/counterexample.c, src/derivation.c: Use max_int instead of max.

src/counterexample.c

@@ -113,11 +113,6 @@ free_counterexample (counterexample *cex)
   free (cex);
 }
 
-static int max (int a, int b)
-{
-  return a < b ? b : a;
-}
-
 static void
 counterexample_print (const counterexample *cex, FILE *out, const char *prefix)
 {
@@ -131,8 +126,8 @@ counterexample_print (const counterexample *cex, FILE *out, const char *prefix)
   const char *deriv2_label
     = cex->shift_reduce ? _("Reduce derivation") : _("Second reduce derivation");
   const int width =
-    max (max (mbswidth (example1_label, 0), mbswidth (example2_label, 0)),
-         max (mbswidth (deriv1_label, 0),   mbswidth (deriv2_label, 0)));
+    max_int (max_int (mbswidth (example1_label, 0), mbswidth (example2_label, 0)),
+             max_int (mbswidth (deriv1_label, 0),   mbswidth (deriv2_label, 0)));
   if (flat)
     fprintf (out, "  %s%s%*s ", prefix,
              example1_label, width - mbswidth (example1_label, 0), "");

src/derivation.c

@@ -135,12 +135,6 @@ derivation_size (const derivation *deriv)
 }
 
 
-static int
-max (int a, int b)
-{
-  return a < b ? b : a;
-}
-
 // Longest distance from root to leaf.
 static int
 derivation_depth (const derivation *deriv)
@@ -154,7 +148,7 @@ derivation_depth (const derivation *deriv)
       for (gl_list_iterator_t it = gl_list_iterator (deriv->children);
            derivation_list_next (&it, &child);
            )
-        res = max (res, derivation_depth (child));
+        res = max_int (res, derivation_depth (child));
       return res + 1;
     }
   else
@@ -237,7 +231,7 @@ derivation_width (const derivation *deriv)
           // No separator at the beginning.
           children_width -= derivation_separator_width;
         }
-      return max (self_width, children_width);
+      return max_int (self_width, children_width);
     }
   else if (deriv == &d_dot)
     {

src/location.c

@@ -40,18 +40,6 @@
 
 location const empty_loc = EMPTY_LOCATION_INIT;
 
-static int
-min_int (int a, int b)
-{
-  return a < b ? a : b;
-}
-
-static int
-max_int (int a, int b)
-{
-  return a >= b ? a : b;
-}
-
 /* The terminal width.  Not less than 40.  */
 static int
 columns (void)

src/system.h

@@ -131,6 +131,22 @@ typedef size_t uintptr_t;
 # include <stdbool.h>
 
 
+/*-----------.
+| Integers.  |
+`-----------*/
+
+static inline int
+min_int (int a, int b)
+{
+  return a < b ? a : b;
+}
+
+static inline int
+max_int (int a, int b)
+{
+  return a >= b ? a : b;
+}
+
 
 /*-------------.
 | Assertions.  |