Bug 9170

Summary:	undefined reference to `cpu_tlb' if used -O0
Product:	Platform Specific/Hardware	Reporter:	liuyj (aboy67)
Component:	ARM	Assignee:	Russell King (rmk)
Status:	REJECTED INVALID
Severity:	low
Priority:	P1
Hardware:	All
OS:	Linux
Kernel Version:	2.6.22	Subsystem:
Regression:	---	Bisected commit-id:

Description liuyj 2007-10-15 23:56:44 UTC

Most recent kernel where this bug did not occur:
Distribution:
Hardware Environment:
Software Environment:
Problem Description:

Steps to reproduce:

in "Linux/include/asm-arm/tlbflush.h" line:186 188
the  "cpu_tlb" should in "#ifdef MULTI_TLB  ... #endif"
in this file and those include it, unuse the "cpu_tlb". 
result : if use -O0 will occurs undefined reference to `cpu_tlb' ,
    but use -Os or -O2 will not occurs.

Comment 1 Russell King 2007-10-16 00:25:45 UTC

The Linux kernel relies upon having an optimising compiler.  -O0 results
in no optimisation.  Always use at least -O1.

Comment 2 Randy Dunlap 2007-10-16 07:56:38 UTC

In my experience, many problems arise when trying to use -O0.  Closed.