The real option name and not the alias used is displayed in msgs when using a config file (#107613)

An example of this is the -mpure-code option. Without a config file
being used, an error message will print `-mpure-code`. But if a config
file is used, the error message will print `-mexecute-only`.

Author: perry-ca

clang/lib/Driver/Driver.cpp

@@ -1005,6 +1005,17 @@ static void appendOneArg(InputArgList &Args, const Arg *Opt,
   Copy->setOwnsValues(Opt->getOwnsValues());
   Opt->setOwnsValues(false);
   Args.append(Copy);
+  if (Opt->getAlias()) {
+    const Arg *Alias = Opt->getAlias();
+    unsigned Index = Args.MakeIndex(Alias->getSpelling());
+    auto AliasCopy = std::make_unique<Arg>(Alias->getOption(),
+                                           Args.getArgString(Index), Index);
+    AliasCopy->getValues() = Alias->getValues();
+    AliasCopy->setOwnsValues(false);
+    if (Alias->isClaimed())
+      AliasCopy->claim();
+    Copy->setAlias(std::move(AliasCopy));
+  }
 }
 
 bool Driver::readConfigFile(StringRef FileName,

clang/test/Driver/arm-execute-only.c

@@ -19,6 +19,9 @@
 
 // RUN: not %clang -### --target=arm-arm-none-eabi -march=armv8-m.main -mpure-code -mno-movt %s 2>&1 \
 // RUN:    | FileCheck %s -check-prefix CHECK-PURE-CODE-NO-MOVT
+// RUN: echo "-DABC"  > %t.cfg
+// RUN: not %clang -### --target=arm-arm-none-eabi -march=armv8-m.main -mpure-code -mno-movt --config %t.cfg %s 2>&1 \
+// RUN:    | FileCheck %s -check-prefix CHECK-PURE-CODE-NO-MOVT
 // CHECK-PURE-CODE-NO-MOVT: error: option '-mpure-code' cannot be specified with '-mno-movt'
 
 // RUN: not %clang -### --target=arm-arm-none-eabi -march=armv6-m -mexecute-only -fropi %s 2>&1 \