[lld] [LLD] [COFF] Print a warning when using /dependentloadflag without load config (PR #117400)

[Martin Storsjö via llvm-commits]

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@@ -29,3 +30,4 @@ FAIL: lld-link: error: /dependentloadflag: invalid argument: zz
 FAIL-RANGE: lld-link: error: /dependentloadflag: invalid argument: 0xf0000
 FAIL-NOARG: lld-link: error: /dependentloadflag: no argument specified
 
+WARN-NOBASE: lld-link: warning: _load_config_used not found, /delayloadflag will have no effect
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mstorsjo wrote:

I needed to remove the `/nodefaultlib` to make it actually do the thing I wanted to test, having `%t.ldcfg-defaultlib.lib` contain a `/defaultlib:` directive, that pulls in another library - with `/nodefaultlib` it would ignore those.

Linking without `/nodefaultlib` doesn't pull in the default CRT libs automatically, only if the object files tells it to. In this case, `%S/Inputs/precomp-a.obj` contains such directives, but I switched that to a different object file for the entry, which doesn't reference `LIBCMT.LIB` and such.

https://github.com/llvm/llvm-project/pull/117400