cmd/cgo/internal/testcshared: Test(Unexported|Exported)Symbols failures with SIGSEGV on android/arm64

#!watchflakes
post <- goos == "android" && pkg == "cmd/cgo/internal/testcshared" && test ~ `Test(Exported|Unexported)Symbols` && `signal: segmentation fault`

Issue created automatically to collect these failures.

Example (log):

--- FAIL: TestExportedSymbols (17.76s)
    cshared_test.go:368: run: [/data/data/com.termux/files/home/clangwrap -fPIC -pthread -fno-caret-diagnostics -Qunused-arguments -Wl,--no-gc-sections -fmessage-length=0 -ffile-prefix-map=/data/data/com.termux/files/home/tmpdir/workdir-host-android-arm64-corellium-android/tmp/go-build1491619758=/tmp/go-build -gno-record-gcc-switches -pie -I pkg/android_arm64 -I /data/data/com.termux/files/home/tmpdir/workdir-host-android-arm64-corellium-android/tmp/testcshared4062456105 -o testp0 main0.c libgo.a]
    cshared_test.go:372: run: [./testp0]
    cshared_test.go:372: command failed: [./testp0]
        signal: segmentation fault

— watchflakes