From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tom Rini Date: Tue, 18 Sep 2012 16:42:52 -0700 Subject: [U-Boot] [PATCH] README.commands: Document what UNDEF_SYM does Message-ID: <1348011772-8533-1-git-send-email-trini@ti.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Signed-off-by: Tom Rini --- doc/README.commands | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/doc/README.commands b/doc/README.commands index 27815d2..21abfb6 100644 --- a/doc/README.commands +++ b/doc/README.commands @@ -22,6 +22,12 @@ This makes it possible for the final link to extract all commands compiled into any object code and construct a static array so the command can be found in an array starting at __u_boot_cmd_start. +To ensure that the linker does not discard these symbols when linking +full U-Boot we use generate a list of all of the commands and force the +linker to first enter the symbol as undefined in the object so that +there is then a need for the symbol to be kept (UNDEF_SYM in the +Makefile). + If a new board is defined do not forget to define the command section by writing in u-boot.lds ($(TOPDIR)/board/boardname/u-boot.lds) these 3 lines: -- 1.7.9.5