http://lists.gnu.org/archive/html/bug-make/2011-04/msg00002.html

Index: read.c
===================================================================
RCS file: /sources/make/make/read.c,v
retrieving revision 1.198
retrieving revision 1.200
diff -u -r1.198 -r1.200
--- read.c	29 Apr 2011 15:27:39 -0000	1.198
+++ read.c	7 May 2011 14:36:12 -0000	1.200
@@ -2901,6 +2901,7 @@
       const char *name;
       const char **nlist = 0;
       char *tildep = 0;
+      int globme = 1;
 #ifndef NO_ARCHIVES
       char *arname = 0;
       char *memname = 0;
@@ -3109,32 +3110,40 @@
	}
 #endif /* !NO_ARCHIVES */

-      switch (glob (name, GLOB_NOSORT|GLOB_ALTDIRFUNC, NULL, &gl))
-	{
-	case GLOB_NOSPACE:
-	  fatal (NILF, _("virtual memory exhausted"));
-
-	case 0:
-          /* Success.  */
-          i = gl.gl_pathc;
-          nlist = (const char **)gl.gl_pathv;
-          break;
-
-        case GLOB_NOMATCH:
-          /* If we want only existing items, skip this one.  */
-          if (flags & PARSEFS_EXISTS)
-            {
-              i = 0;
-              break;
-            }
-          /* FALLTHROUGH */
-
-	default:
-          /* By default keep this name.  */
+      /* glob() is expensive: don't call it unless we need to.  */
+      if (!(flags & PARSEFS_EXISTS) && strpbrk (name, "?*[") == NULL)
+        {
+          globme = 0;
           i = 1;
           nlist = &name;
-          break;
-	}
+        }
+      else
+        switch (glob (name, GLOB_NOSORT|GLOB_ALTDIRFUNC, NULL, &gl))
+          {
+          case GLOB_NOSPACE:
+            fatal (NILF, _("virtual memory exhausted"));
+
+          case 0:
+            /* Success.  */
+            i = gl.gl_pathc;
+            nlist = (const char **)gl.gl_pathv;
+            break;
+
+          case GLOB_NOMATCH:
+            /* If we want only existing items, skip this one.  */
+            if (flags & PARSEFS_EXISTS)
+              {
+                i = 0;
+                break;
+              }
+            /* FALLTHROUGH */
+
+          default:
+            /* By default keep this name.  */
+            i = 1;
+            nlist = &name;
+            break;
+          }

       /* For each matched element, add it to the list.  */
       while (i-- > 0)
@@ -3174,7 +3183,8 @@
 #endif /* !NO_ARCHIVES */
           NEWELT (concat (2, prefix, nlist[i]));

-      globfree (&gl);
+      if (globme)
+        globfree (&gl);

 #ifndef NO_ARCHIVES
       if (arname)
Index: tests/scripts/functions/wildcard
===================================================================
RCS file: /sources/make/make/tests/scripts/functions/wildcard,v
retrieving revision 1.6
retrieving revision 1.7
diff -u -r1.6 -r1.7
--- tests/scripts/functions/wildcard	13 Jun 2009 21:21:49 -0000	1.6
+++ tests/scripts/functions/wildcard	7 May 2011 14:36:11 -0000	1.7
@@ -88,4 +88,16 @@
 !,
               '', "\n");

+# TEST #5: wildcard used to verify file existence
+
+touch('xxx.yyy');
+
+run_make_test(q!exists: ; @echo file=$(wildcard xxx.yyy)!,
+              '', "file=xxx.yyy\n");
+
+unlink('xxx.yyy');
+
+run_make_test(q!exists: ; @echo file=$(wildcard xxx.yyy)!,
+              '', "file=\n");
+
 1;