[clang] [flang] [flang][driver] Avoid mentions of Clang in Flang's command line reference. (PR #88932)

[Michael Kruse via cfe-commits]

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@@ -807,8 +807,12 @@ def gcc_install_dir_EQ : Joined<["--"], "gcc-install-dir=">,
   "Note: executables (e.g. ld) used by the compiler are not overridden by the selected GCC installation">;
 def gcc_toolchain : Joined<["--"], "gcc-toolchain=">, Flags<[NoXarchOption]>,
   Visibility<[ClangOption, FlangOption]>,
-  HelpText<"Specify a directory where Clang can find 'include' and 'lib{,32,64}/gcc{,-cross}/$triple/$version'. "
-  "Clang will use the GCC installation with the largest version">;
+  HelpText<
+    "Specify a directory where Clang can find 'include' and 'lib{,32,64}/gcc{,-cross}/$triple/$version'. "
+    "Clang will use the GCC installation with the largest version">,
+  HelpTextForVariants<[FlangOption],
+    "Specify a directory where Flang can find 'lib{,32,64}/gcc{,-cross}/$triple/$version'. "
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Meinersbur wrote:

Even though flang has a (non-standard) preprocessor, it doesn't add `-isystem` includes from gcc's dir. Hence referencing `include` could be confusing.

https://github.com/llvm/llvm-project/pull/88932