Submitted By: Jim Gifford (patches at jg555 dot com)
Date: 2003-09-12
Initial Package Version: 3.80
Origin: http://savannah.gnu.org/bugs/?func=detailbug&bug_id=1517&group_id=71
Description: Using $(eval ...) can lead to fatal errors about allocating too
	     much memory, or it can evaluate to a value (the manual says it
	     always evaluates to the empty string). See: 

e0 = $(foreach s,foobar,$(eval $s:)) 
e1 = $(foreach s,foobar, $(eval $s:)) 

all: ; @echo e0 == $(e0) e1 == $(e1) 

$ make 
e0 == e1 == f 

The e0 value is correct, but e1 is wrong.

diff -Naur make-3.80.orig/expand.c make-3.80/expand.c
--- make-3.80.orig/expand.c	2002-07-11 06:38:57.000000000 +0000
+++ make-3.80/expand.c	2003-09-12 06:09:50.000000000 +0000
@@ -564,3 +564,28 @@
 
   return value;
 }
+
+/* Install a new variable_buffer context, returning the current one for
+   safe-keeping.  */
+
+void
+install_variable_buffer (char **bufp, unsigned int *lenp)
+{
+  *bufp = variable_buffer;
+  *lenp = variable_buffer_length;
+
+  variable_buffer = 0;
+  initialize_variable_output ();
+}
+
+/* Restore a previously-saved variable_buffer setting (free the current one).
+ */
+
+void
+restore_variable_buffer (char *buf, unsigned int len)
+{
+  free (variable_buffer);
+
+  variable_buffer = buf;
+  variable_buffer_length = len;
+}
diff -Naur make-3.80.orig/function.c make-3.80/function.c
--- make-3.80.orig/function.c	2002-10-04 02:13:42.000000000 +0000
+++ make-3.80/function.c	2003-09-12 06:09:50.000000000 +0000
@@ -1281,8 +1281,18 @@
      char **argv;
      const char *funcname;
 {
+  char *buf;
+  unsigned int len;
+
+  /* Eval the buffer.  Pop the current variable buffer setting so that the
+     eval'd code can use its own without conflicting.  */
+
+  install_variable_buffer (&buf, &len);
+
   eval_buffer (argv[0]);
 
+  restore_variable_buffer (buf, len);
+
   return o;
 }
 
diff -Naur make-3.80.orig/variable.h make-3.80/variable.h
--- make-3.80.orig/variable.h	2002-08-08 00:11:19.000000000 +0000
+++ make-3.80/variable.h	2003-09-12 06:09:50.000000000 +0000
@@ -107,6 +107,8 @@
 extern char *expand_argument PARAMS ((char *str, char *end));
 extern char *variable_expand_string PARAMS ((char *line, char *string,
                                              long length));
+extern void install_variable_buffer PARAMS ((char **bufp, unsigned int *lenp));
+extern void restore_variable_buffer PARAMS ((char *buf, unsigned int len));
 
 /* function.c */
 extern int handle_function PARAMS ((char **op, char **stringp));