[U-Boot] [PATCH v2 1/5] fdt: boot_get_fdt: remove redundant zeroing out

Eugeniu Rosca erosca at de.adit-jv.com
Mon Apr 1 10:45:33 UTC 2019


Paranoid programming [1] lies at the foundation of proper software
development, but the repetitive zeroing-out of output arguments in the
context of the same function rather clutters the code and inhibits
further refactoring/optimization than is doing any good.

In boot_get_fdt(), we already perform zero/NULL-initialization of
*of_flat_tree and *of_size at the beginning of the function, so doing
the same at function error-out is redundant/superfluous.

Moreover, keeping the code unchanged might encourage the developers to
update *of_flat_tree and *of_size during some interim computations,
which is against the current design of boot_get_fdt(). Currently,
writing useful data into these arguments happens just before
successfully returning from boot_get_fdt() and it should better stay so.

[1] https://blog.regehr.org/archives/1106

Signed-off-by: Eugeniu Rosca <erosca at de.adit-jv.com>
---
Changes in v2:
 - s/zeroint-out/zeroing-out/ in commit description
 - Link v1: https://patchwork.ozlabs.org/patch/1071586/
---
 common/image-fdt.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/common/image-fdt.c b/common/image-fdt.c
index 01186aeac7a4..1817ce6bce30 100644
--- a/common/image-fdt.c
+++ b/common/image-fdt.c
@@ -489,8 +489,6 @@ int boot_get_fdt(int flag, int argc, char * const argv[], uint8_t arch,
 no_fdt:
 	ok_no_fdt = 1;
 error:
-	*of_flat_tree = NULL;
-	*of_size = 0;
 	if (!select && ok_no_fdt) {
 		debug("Continuing to boot without FDT\n");
 		return 0;
-- 
2.21.0



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