diff options
| author | Tom Rini <trini@ti.com> | 2012-09-20 06:02:43 +0000 |
|---|---|---|
| committer | Tom Rini <trini@ti.com> | 2012-09-26 11:08:32 -0700 |
| commit | 2d1d65838eacd314b989701bd2f9e2b657bbf62b (patch) | |
| tree | 25644feecf696bc101c9be34f6a69329845ee817 /doc | |
| parent | 244e6f97055aa86e446ed3a925fdfa3f2b8f8207 (diff) | |
README.commands: Document what UNDEF_SYM does
Changes in v2:
- Reword a bit more
Signed-off-by: Tom Rini <trini@ti.com>
Diffstat (limited to 'doc')
| -rw-r--r-- | doc/README.commands | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/doc/README.commands b/doc/README.commands index 27815d2ba18..125f077c08f 100644 --- a/doc/README.commands +++ b/doc/README.commands @@ -22,6 +22,13 @@ 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 generate a list of all the commands we have built (based +on the sections mentioned above) and use that to force the linker to +first enter the symbol as undefined in the output object so that there +is then a need for the symbol to be kept (this is the UNDEF_SYM logic 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: |