[PATCH] Add reference to implicit use in _bfd_elf_is_local_label_name.

[Jim Wilson]

As discussed, adding Nick's rewritten FAKE_LABEL_CHAR comment.  Committed.

	gas/
	* write.h (FAKE_LABEL_CHAR): Expand comment.
---
 gas/write.h | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/gas/write.h b/gas/write.h
index 4157bc971c..d2c6af6824 100644
--- a/gas/write.h
+++ b/gas/write.h
@@ -27,8 +27,15 @@
 #define FAKE_LABEL_NAME "L0\001"
 #endif
 
-/* This is the special character used to indicate a fake symbol.  Must be
-   present in FAKE_LABEL_NAME.  */
+/* This is a special character that is used to indicate a fake label.
+   It must be present in FAKE_LABEL_NAME, although it does not have to
+   be the first character.  It must not be a character that would be
+   found in a valid symbol name.
+
+   Also be aware that the function _bfd_elf_is_local_label_name in
+   bfd/elf.c has an implicit assumption that FAKE_LABEL_CHAR is '\001'.
+   If this is not the case then FAKE_LABEL_NAME must start with ".L" in
+   order for the function to continue working.  */
 #ifndef FAKE_LABEL_CHAR
 #define FAKE_LABEL_CHAR '\001'
 #endif
-- 
2.14.1