cmd/objdump: TestDisasmCode fails with "no runtime.symtab symbol found" on AIX

[alexbrainman]

I just submitted https://go-review.googlesource.com/c/go/+/240957

The CL broke aix-ppc64 build https://build.golang.org/log/75e953b5afd44cd7dc7cd40db4f7c3d5ab0f853b

--- FAIL: TestDisasmCode (4.49s)
    objdump_test.go:145: Running [/ramdisk8GB/workdir-host-aix-ppc64-osuosl/go/bin/go build -o /ramdisk8GB/workdir-host-aix-ppc64-osuosl/tmp/TestObjDump902713307/hello-7f184b50e2cba293836d4b2309588185.exe fmthello.go]
    objdump_test.go:198: Running [/ramdisk8GB/workdir-host-aix-ppc64-osuosl/tmp/TestObjDump902713307/testobjdump.exe -S -s main.main /ramdisk8GB/workdir-host-aix-ppc64-osuosl/tmp/TestObjDump902713307/hello-7f184b50e2cba293836d4b2309588185.exe]
    objdump_test.go:145: Running [/ramdisk8GB/workdir-host-aix-ppc64-osuosl/go/bin/go build -o /ramdisk8GB/workdir-host-aix-ppc64-osuosl/tmp/TestObjDump902713307/hello-50c34f7265eea30b52665e483079b0c1.exe fmthellocgo.go]
    objdump_test.go:198: Running [/ramdisk8GB/workdir-host-aix-ppc64-osuosl/tmp/TestObjDump902713307/testobjdump.exe -S -s main.main /ramdisk8GB/workdir-host-aix-ppc64-osuosl/tmp/TestObjDump902713307/hello-50c34f7265eea30b52665e483079b0c1.exe]
    objdump_test.go:202: objdump "fmthellocgo.exe": exit status 1
        objdump: disassemble /ramdisk8GB/workdir-host-aix-ppc64-osuosl/tmp/TestObjDump902713307/hello-50c34f7265eea30b52665e483079b0c1.exe: no runtime.symtab symbol found
--- FAIL: TestDisasm (4.50s)
    objdump_test.go:145: Running [/ramdisk8GB/workdir-host-aix-ppc64-osuosl/go/bin/go build -o /ramdisk8GB/workdir-host-aix-ppc64-osuosl/tmp/TestObjDump902713307/hello-ea6f791f716c96f8441f99ba474a41f0.exe fmthello.go]
    objdump_test.go:198: Running [/ramdisk8GB/workdir-host-aix-ppc64-osuosl/tmp/TestObjDump902713307/testobjdump.exe -s main.main /ramdisk8GB/workdir-host-aix-ppc64-osuosl/tmp/TestObjDump902713307/hello-ea6f791f716c96f8441f99ba474a41f0.exe]
    objdump_test.go:145: Running [/ramdisk8GB/workdir-host-aix-ppc64-osuosl/go/bin/go build -o /ramdisk8GB/workdir-host-aix-ppc64-osuosl/tmp/TestObjDump902713307/hello-a6acfb7e9d32782fea9814ad1314bef1.exe fmthellocgo.go]
    objdump_test.go:198: Running [/ramdisk8GB/workdir-host-aix-ppc64-osuosl/tmp/TestObjDump902713307/testobjdump.exe -s main.main /ramdisk8GB/workdir-host-aix-ppc64-osuosl/tmp/TestObjDump902713307/hello-a6acfb7e9d32782fea9814ad1314bef1.exe]
    objdump_test.go:202: objdump "fmthellocgo.exe": exit status 1
        objdump: disassemble /ramdisk8GB/workdir-host-aix-ppc64-osuosl/tmp/TestObjDump902713307/hello-a6acfb7e9d32782fea9814ad1314bef1.exe: no runtime.symtab symbol found
--- FAIL: TestDisasmGnuAsm (4.51s)
    objdump_test.go:145: Running [/ramdisk8GB/workdir-host-aix-ppc64-osuosl/go/bin/go build -o /ramdisk8GB/workdir-host-aix-ppc64-osuosl/tmp/TestObjDump902713307/hello-a2fdf6fa5e30e7eb2b8d7d63be13b362.exe fmthello.go]
    objdump_test.go:198: Running [/ramdisk8GB/workdir-host-aix-ppc64-osuosl/tmp/TestObjDump902713307/testobjdump.exe -gnu -s main.main /ramdisk8GB/workdir-host-aix-ppc64-osuosl/tmp/TestObjDump902713307/hello-a2fdf6fa5e30e7eb2b8d7d63be13b362.exe]
    objdump_test.go:145: Running [/ramdisk8GB/workdir-host-aix-ppc64-osuosl/go/bin/go build -o /ramdisk8GB/workdir-host-aix-ppc64-osuosl/tmp/TestObjDump902713307/hello-739d837da95c25909d2915651b14619d.exe fmthellocgo.go]
    objdump_test.go:198: Running [/ramdisk8GB/workdir-host-aix-ppc64-osuosl/tmp/TestObjDump902713307/testobjdump.exe -gnu -s main.main /ramdisk8GB/workdir-host-aix-ppc64-osuosl/tmp/TestObjDump902713307/hello-739d837da95c25909d2915651b14619d.exe]
    objdump_test.go:202: objdump "fmthellocgo.exe": exit status 1
        objdump: disassemble /ramdisk8GB/workdir-host-aix-ppc64-osuosl/tmp/TestObjDump902713307/hello-739d837da95c25909d2915651b14619d.exe: no runtime.symtab symbol found
FAIL
FAIL	cmd/objdump	6.060s
FAIL
go tool dist: Failed: exit status 1

The CL changes Windows specific code. But it extended the test to include testing against cgo binaries. And that feature appears to broken on AIX. I don't know how to fix the feature, but I will disable new test code for AIX in the meantime.

Alex

[gopherbot]

Change https://golang.org/cl/249760 mentions this issue: cmd/objdump: skip cgo test in testGoAndCgoDisasm on AIX

[Helflym]

These errors are expected. Cgo programs are linked using external linker on AIX, and objdump doesn't seem to work with ppc64 and external linker (cf TestDisasmExtld)

[aclements]

Is there an actual bug to track at this point? If this isn't expected to work, then we should close this since the test is now disabled on AIX. Or is the bug that objdump doesn't work with externally linked binaries on AIX?

[Helflym]

I didn't have time to investigate further. But the bug is triggered because runtime.symtab is not found. AIX linker seems to think this symbol along with runtime.esymtab is not needed (or at least not reached), thus it removes it from the final link.
Thus, the whole command objdump doesn't work with AIX externally linked programs.