Why is Visual Studio on Compiler Explorer ignoring the Exception Model setting?

Question

When I try to use the /EHs flag in a Compiler Explorer testcase (to "enable" exceptions passing through extern "C" functions), VC++ 19.22 seems to be ignoring it, based on it still kicking out a C5039 and not actually changing the code.

What am I missing? Have I forgotten another switch or something?

Base case cmdline: /O1 /EHsc /Wall /wd4571
Test case cmdline: /O1 /EHs /Wall /wd4571

SO you've found/fixed the problem … BUT, do you now get different code generated? (The stuff I tried yesterday on your related issue always gave the same generated ASM, no matter what use of /EH I tried.) — Adrian Mole, Nov 26 '19 at 12:29
@Adrian-ReinstateMonica I haven't fixed the problem yet sadly; I'm not sure there's a way to override that flag, so I've asked Matt whether he can make it conditional or something. FWIW, I was able to prove externally that the approach works ... _but_ I've yet to produce a useful self-contained testcase online. This question was generated by my getting back into that - watch this space :) — Lightness Races in Orbit, Nov 26 '19 at 12:30

score 4 · Answer 1 · answered Nov 26 '19 at 12:22

4

Ah, looks like Compiler Explorer sets the exception model itself, and this is taking precedence.

answered Nov 26 '19 at 12:22

Lightness Races in Orbit

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Good ol' freehand red circles! – Max Langhof Nov 26 '19 at 12:37
@MaxLanghof Really? All I can see is `Screenshot of the culprit`. (Damn company firewall.) ;-) (Although, I'm happier to see this than the usual _Enter image description here._) – Scheff's Cat Nov 26 '19 at 12:38
@Scheff Is [this archive.org screenshot](http://web.archive.org/web/20191126124038/http://web.archive.org/screenshot/https://stackoverflow.com/questions/59050839/why-is-visual-studio-on-compiler-explorer-ignoring-the-exception-model-setting/59050911?noredirect=1) allowed? ;) – Max Langhof Nov 26 '19 at 12:41
@MaxLanghof Nope. Same issue: Content blocked. (Thanks for your effort but, please, don't waste your time. I'm used to it.) – Scheff's Cat Nov 26 '19 at 12:42
@Scheff Blimey! – Lightness Races in Orbit Nov 26 '19 at 12:52
@Scheff I tried converting it to SVG for you, but [it didn't go very well](https://jsfiddle.net/gw6ptqbk/) – Lightness Races in Orbit Nov 26 '19 at 12:58
It doesn't look like Compiler Explorer anymore. However, I consider to print it and add it to my wall decoration in office. (Currently, most of the wall is covered with XKCD comics...) – Scheff's Cat Nov 26 '19 at 12:59
Warm thanks. You already got my votes to pay back for your effort. I will ask our engineers whether I could (ab)use their A0 plotter... – Scheff's Cat Nov 26 '19 at 13:06
@Scheff Sounds good Be sure to take a photo and put it on, er, imgur... okay perhaps an ASCII art version then – Lightness Races in Orbit Nov 26 '19 at 13:07

Why is Visual Studio on Compiler Explorer ignoring the Exception Model setting?

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