[PATCH 4/7] ARM: io-acorn: fix LTO linking without CONFIG_PRINTK

Arnd Bergmann arnd at arndb.de
Tue Feb 20 13:59:51 PST 2018

When CONFIG_LTO is enabled, we get a link error for this file
that contains a reference to printk():

arch/arm/lib/io-acorn.o: In function `outsl':
(.text+0x38): undefined reference to `printk'

Normally the file is simply dropped, but that doesn't happen
with LTO. Making the reference conditional helps, but perhaps
a better fix would be to make sure the LTO linker drops the
entire file in the same way that we normally do.

Signed-off-by: Arnd Bergmann <arnd at arndb.de>
 arch/arm/lib/io-acorn.S | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/arch/arm/lib/io-acorn.S b/arch/arm/lib/io-acorn.S
index 69719bad674d..3522a899460b 100644
--- a/arch/arm/lib/io-acorn.S
+++ b/arch/arm/lib/io-acorn.S
@@ -27,6 +27,10 @@
 		adr	r0, .Liosl_warning
 		mov	r1, lr
 		b	printk
+		ret	lr

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