From http://sources.redhat.com/cgi-bin/cvsweb.cgi/src/gas/config/tc-arm.c.diff?r1=1.168&r2=1.169&cvsroot=src
See also http://lists.arm.linux.org.uk/pipermail/linux-arm-kernel/2004-July/023128.html,
"[CRITICAL PATCH] 2.6: fix silent build error]"

Revision 1.169, Fri Jul 2 11:12:29 2004 UTC (19 hours, 4 minutes ago) by nickc
Branch: MAIN
CVS Tags: binutils_latest_snapshot, HEAD
Changes since 1.168: +14 -1 lines

(md_apply_fix3:BFD_RELOC_ARM_IMMEDIATE): Do not allow values which have come
from undefined symbols.
Always consider this fixup to have been processed as a reloc cannot be
generated for it.


===================================================================
RCS file: /cvs/src/src/gas/config/tc-arm.c,v
retrieving revision 1.168
retrieving revision 1.169
diff -u -r1.168 -r1.169
--- src/gas/config/tc-arm.c	2004/04/30 10:51:12	1.168
+++ src/gas/config/tc-arm.c	2004/07/02 11:12:29	1.169
@@ -12186,6 +12186,20 @@
   switch (fixP->fx_r_type)
     {
     case BFD_RELOC_ARM_IMMEDIATE:
+      /* We claim that this fixup has been processed here,
+	 even if in fact we generate an error because we do
+	 not have a reloc for it, so tc_gen_reloc will reject it.  */
+      fixP->fx_done = 1;
+
+      if (fixP->fx_addsy
+	  && ! S_IS_DEFINED (fixP->fx_addsy))
+	{
+	  as_bad_where (fixP->fx_file, fixP->fx_line,
+			_("undefined symbol %s used as an immediate value"),
+			S_GET_NAME (fixP->fx_addsy));
+	  break;
+	}
+
       newimm = validate_immediate (value);
       temp = md_chars_to_number (buf, INSN_SIZE);
 
@@ -12202,7 +12216,6 @@
 
       newimm |= (temp & 0xfffff000);
       md_number_to_chars (buf, (valueT) newimm, INSN_SIZE);
-      fixP->fx_done = 1;
       break;
 
     case BFD_RELOC_ARM_ADRL_IMMEDIATE: