[LLD] [MinGW] Implement --dependent-load-flag option (#113814)

Implement MSVC's `/DEPENDENTLOADFLAG` as `--dependent-load-flag` and
forward it to COFF.

ld.bfd doesn't support it, yet at least, but if they later add support for something similar, hopefully they’d agree to the same option name.

There is no solid need for it yet, but it's being considered:
msys2/MINGW-packages#22216 (comment)

Author: mati865

lld/MinGW/Driver.cpp

@@ -407,6 +407,9 @@ bool link(ArrayRef<const char *> argsArr, llvm::raw_ostream &stdoutOS,
                    OPT_no_allow_multiple_definition, false))
     add("-force:multiple");
 
+  if (auto *a = args.getLastArg(OPT_dependent_load_flag))
+    add("-dependentloadflag:" + StringRef(a->getValue()));
+
   if (auto *a = args.getLastArg(OPT_icf)) {
     StringRef s = a->getValue();
     if (s == "all")

lld/MinGW/Options.td

@@ -202,6 +202,7 @@ def _HASH_HASH_HASH : Flag<["-"], "###">,
     HelpText<"Print (but do not run) the commands to run for this compilation">;
 def appcontainer: F<"appcontainer">, HelpText<"Set the appcontainer flag in the executable">;
 defm delayload: Eq<"delayload", "DLL to load only on demand">;
+defm dependent_load_flag: EEq<"dependent-load-flag", "Override default LibraryLoad flags">;
 defm mllvm: EqNoHelp<"mllvm">;
 defm pdb: Eq<"pdb", "Output PDB debug info file, chosen implicitly if the argument is empty">;
 defm Xlink : Eq<"Xlink", "Pass <arg> to the COFF linker">, MetaVarName<"<arg>">;

lld/test/MinGW/driver.test

@@ -462,3 +462,6 @@ RUN: ld.lld -### foo.o -m i386pep --rpath foo 2>&1 | FileCheck -check-prefix=WAR
 RUN: ld.lld -### foo.o -m i386pep -rpath=foo 2>&1 | FileCheck -check-prefix=WARN_RPATH %s
 RUN: ld.lld -### foo.o -m i386pep --rpath=foo 2>&1 | FileCheck -check-prefix=WARN_RPATH %s
 WARN_RPATH: warning: parameter -{{-?}}rpath has no effect on PE/COFF targets
+
+RUN: ld.lld -### foo.o -m i386pe --dependent-load-flag=0x800 2>&1 | FileCheck -check-prefix=DEPENDENT_LOAD_FLAG %s
+DEPENDENT_LOAD_FLAG: -dependentloadflag:0x800