src: init emit_env_nonstring_warning_

[danbev]

Currently there is no member initialiser for emit_env_nonstring_warning_
in the Environment constructor leading to undefined behaviour.
For a debug build, this memory would be initialized:

(lldb) memory read -f x -s 4 -c 1 &emit_env_nonstring_warning_
0x7fff5fbfe254: 0x00000001

But for a release build there will be no such initialization:

(lldb) memory read -f x -s 4 -c 1 `$r12 + 0x46c`
0x7fff5fbfe374: 0x00000000

This can be seen by running test-process-env-deprecation.js using
the Debug build and the Release build.

This commit adds a member initialiser for emit_env_nonstring_warning_
setting it to true.

Checklist

• make -j4 test (UNIX), or vcbuild test (Windows) passes
• commit message follows commit guidelines

[danbev]

CI: https://ci.nodejs.org/job/node-test-pull-request/13621/

[danbev]

node-test-commit-freebsd failure looks unrelated

console output:

not ok 708 parallel/test-http-client-timeout-agent
  ---
  duration_ms: 1.695
  severity: fail
  stack: |-
    res#0 data:0
    res#0 end
    res#2 data:2
    res#2 end
    res#4 data:4
    res#4 end
    res#6 data:6
    res#6 end
    res#8 data:8
    res#8 end
    res#10 data:10
    res#10 end
    res#12 data:12
    res#12 end
    res#14 data:14
    res#14 end
    res#16 data:16
    res#16 end
    res#18 data:18
    res#18 end
    res#20 data:20
    res#20 end
    res#22 data:22
    res#22 end
    res#24 data:24
    res#24 end
    res#26 data:26
    res#26 end
    res#28 data:28
    res#28 end
    req#1 timeout
    req#3 timeout
    req#5 timeout
    req#7 timeout
    req#9 timeout
    req#11 timeout
    req#13 timeout
    req#15 timeout
    req#17 timeout
    req#19 timeout
    req#21 timeout
    req#23 timeout
    req#25 timeout
    req#27 timeout
    req#29 timeout
    req#0 timeout
    req#2 timeout
    req#4 timeout
    req#6 timeout
    req#8 timeout
    req#10 timeout
    req#12 timeout
    req#14 timeout
    req#16 timeout
    req#18 timeout
    req#20 timeout
    req#22 timeout
    req#24 timeout
    req#26 timeout
    req#28 timeout
    req#28 close
    req#26 close
    req#24 close
    req#22 close
    req#20 close
    req#18 close
    req#16 close
    req#14 close
    req#12 close
    req#10 close
    req#8 close
    req#6 close
    req#4 close
    req#2 close
    req#0 close
    req#29 error
    req#29 close
    req#27 error
    req#27 close
    req#25 error
    req#25 close
    req#23 error
    req#23 close
    req#21 error
    req#21 close
    req#19 error
    req#19 close
    req#17 error
    req#17 close
    req#15 error
    req#15 close
    req#13 error
    req#13 close
    req#11 error
    req#11 close
    req#9 error
    req#9 close
    req#7 error
    req#7 close
    req#5 error
    req#5 close
    req#3 error
    req#3 close
    req#1 error
    req#1 close
    done=45 sent=30
    assert.js:80
      throw new AssertionError(obj);
      ^
    
    AssertionError [ERR_ASSERTION]: timeout on http request called too much
        at process.<anonymous> (/usr/home/iojs/build/workspace/node-test-commit-freebsd/nodes/freebsd10-64/test/parallel/test-http-client-timeout-agent.js:94:10)
        at process.emit (events.js:187:15)
  ...

[danbev]

@addaleax Do you think this should be fast-tracked perhaps? It is causing all new PR to fail at the moment.

[cjihrig]

I think we should fast track this.

[danbev]

Landed in a7e298a

[MylesBorins]

Should this be backported to v9.x-staging? If yes please follow the guide and raise a backport PR, if not let me know or add the dont-land-on label.

[MylesBorins]

Should this be backported to v8.x? It fails to compile with the following warning

../src/env.cc:89:7: error: member initializer 'emit_env_nonstring_warning_' does not name a non-static data member or base class
      emit_env_nonstring_warning_(true),
      ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1 error generated.
make[1]: *** [/Users/mborins/code/node/v8.x/out/Release/obj.target/node_lib/src/env.o] Error 1