https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86064
Bug ID: 86064
Summary: [8 Regression] compiling Linux kernel: Error: can't
resolve `.text.unlikely' {.text.unlikely section} -
`.LVL43x' {.text section}
Product: gcc
Version: 8.1.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c
Assignee: unassigned at gcc dot gnu.org
Reporter: alex_y_xu at yahoo dot ca
Target Milestone: ---
description:
compiling Linux kernel fails with gcc 8.1. I think gcc 7.3.1-20180406 works.
steps to reproduce:
gcc -fno-var-tracking-assignments -gsplit-dwarf -O2 -c -o /dev/null -c common.i
flags trimmed from full compile line. file preprocessed from
linux-4.17/arch/x86/kernel/cpu/common.c.
expected result:
objcopy: Warning: '/dev/null' is not an ordinary file
actual result:
Assembler messages:
Error: can't resolve `.text.unlikely' {.text.unlikely section} - `.LVL436'
{.text section}
Error: can't resolve `.text.unlikely' {.text.unlikely section} - `.LVL437'
{.text section}
additional information:
-O1 compiles with no errors. -O0 produces the following (trimmed):
./arch/x86/include/asm/cpufeature.h: In function ‘syscall_init’:
./arch/x86/include/asm/cpufeature.h:164:7: warning: asm operand 0 probably
doesn’t match constraints
asm_volatile_goto("1: jmp 6f\n"
^~~
./arch/x86/include/asm/cpufeature.h:164:7: warning: asm operand 2 probably
doesn’t match constraints
./arch/x86/include/asm/cpufeature.h:164:7: error: impossible constraint in
‘asm’
you can find the contents of cpufeature.h in the Linux source code.
.config available on request.
