Catch EMS variables initialized after reference

[joseph-robertson]

Pull request overview

• Fixes Unitialized EMS variable is misused #11360

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[mitchute]

As I understand it, Windows builds don't pick up uninitialized variables, which we treat as errors.

/home/mitchute/Projects/EnergyPlus/tst/EnergyPlus/unit/EMSManager.unit.cc:1065:9: error: unused variable ‘wallSurfNum’ [-Werror=unused-variable]
 1065 |     int wallSurfNum = Util::FindItemInList("WALL", state->dataSurface->Surface);
      |         ^~~~~~~~~~~

[rraustad]

I am using Windows 11 and do not get the unused variable warning for wallSurfNum, well, because it is initialized at line 1065 and used at 1068. If there is an issue with EMS initializing a variable before it's used (e.g., site_temp_adj) then this unit test should fail. But it doesn't, it passes with. wallSurfNum = 1, ViewFactorGround = 0.1 and seriousErrorFound = false (i.e., EXPECT_TRUE on line 1076 should be EXPECT_FASLE and line 1068 is correct). So what should happen here? I assume this unit test should check for whether site_temp_adj was initialized before it was used, but I don't see that in this unit test.

[joseph-robertson]

This PR is about the EMS variable site_temp_adj, not wallSurfNum. The intent (i.e., 8623d71) was to commit a failing test, to demonstrate that the uninitialized site_temp_adj should throw an error but does not. The test fails on my machine.

[joseph-robertson]

Variable site_temp_adj is being initialized after it is referenced. We should expect an error, right?

[joseph-robertson]

I intentionally had this line commented out so that we could get to EXPECT_TRUE(seriousErrorFound); down below.

[mitchute]

Sure, feel free to do what you need. I won't interfere anymore until you need someone to look. I was just pointing out that the CI linux builds were failing due to to the unused variable, that we treat as an error.

[joseph-robertson]

No problem, understood.

[joseph-robertson]

Pretty sure I have this narrowed down. I think GetEMSInput can set state.dataRuntimeLang->ErlVariable(VariableNum).Value.initialized = true without calling EvaluateExpression first.

[joseph-robertson]

This is the main difference with the first test; why is this suddenly initialized?