Go link tool need to find gcc on Arm platform

[lubinszARM]

Signed-off-by: Bin Lu [email protected]

[lubinszARM]

Hi all,
I added a workaround for go link on Arm platform.
On Arm platform, go link tool need some features of gcc to complete the job, but on x86 platform, go link tool does not need gcc.
So, I added the path for 'gcc' in the patch. If without this patch, google/gvisor will be compiled failed on Arm platform.
Please see my test log as more reference:

On Arm platform:

root@bin:/home/bblu/test# exec env - /bin/bash -c '/usr/local/go/bin/go tool link -s -v -o test test.a'
HEADER = -H4 -T0x11000 -D0x0 -R0x10000
searching for runtime.a in /usr/local/go/pkg/linux_arm64/runtime.a
0.00 deadcode
0.02 pclntab=612447 bytes, funcdata total 118962 bytes
0.03 dodata
0.03 dwarf
0.05 symsize = 0
0.08 reloc
0.10 asmb
0.10 datblk
0.11 sym
0.11 elfsym
0.11 symsize = 121488
0.11 symsize = 122016
0.13 header
0.14 host link: "gcc" "-s" "-o" "test" "-rdynamic" "/tmp/go-link-335745272/go.o" "/tmp/go-link-335745272/000000.o" "/tmp/go-link-335745272/000001.o" "/tmp/go-link-335745272/000002.o" "/tmp/go-link-335745272/000003.o" "/tmp/go-link-335745272/000004.o" "/tmp/go-link-335745272/000005.o" "/tmp/go-link-335745272/000006.o" "/tmp/go-link-335745272/000007.o" "/tmp/go-link-335745272/000008.o" "/tmp/go-link-335745272/000009.o" "/tmp/go-link-335745272/000010.o" "/tmp/go-link-335745272/000011.o" "/tmp/go-link-335745272/000012.o" "/tmp/go-link-335745272/000013.o" "-g" "-O2" "-g" "-O2" "-lpthread"
/usr/local/go/pkg/tool/linux_arm64/link: running gcc failed: exec: "gcc": executable file not found in $PATH

---

On X86 platform:

root@os:~/bblu/test# exec env - /bin/bash -c '/usr/local/go/bin/go tool link -s -v -o test test.a'
HEADER = -H4 -T0x401000 -D0x0 -R0x1000
searching for runtime.a in /usr/local/go/pkg/linux_amd64/runtime.a
0.00 deadcode
0.03 pclntab=624716 bytes, funcdata total 116096 bytes
0.03 dodata
0.03 dynreloc
0.04 reloc
0.04 asmb
0.04 codeblk
0.05 rodatblk
0.05 datblk
0.05 headr
0.05 cpu time
47771 symbols
68020 liveness data

[jayconrod]

Thanks!