Linking: Preserve nested LINKER: prefixes as written

Previously LINKER:,-Xlinker and -Wl, options nested inside LINKER:
prefixes would be transformed to separate prefixed options.
This is confusing and undocumented behavior, instead preserve these
as written.

Fixes: #26298

1 files changed, 31 insertions, 15 deletions

diff --git a/Source/cmGeneratorTarget_Options.cxx b/Source/cmGeneratorTarget_Options.cxx
index df22b90..d8b3eb3 100644
--- a/Source/cmGeneratorTarget_Options.cxx
+++ b/Source/cmGeneratorTarget_Options.cxx
@@ -7,6 +7,7 @@
 #include "cmConfigure.h"
 
 #include <algorithm>
+#include <iterator>
 #include <map>
 #include <memory>
 #include <string>
@@ -91,10 +92,16 @@ void processOptions(cmGeneratorTarget const* tgt,
   }
 }
 
+enum class NestedLinkerFlags
+{
+  PreserveAsSpelled,
+  Normalize,
+};
+
 std::vector<BT<std::string>> wrapOptions(
   std::vector<std::string>& options, const cmListFileBacktrace& bt,
   const std::vector<std::string>& wrapperFlag, const std::string& wrapperSep,
-  bool concatFlagAndArgs)
+  bool concatFlagAndArgs, NestedLinkerFlags nestedLinkerFlags)
 {
   std::vector<BT<std::string>> result;
 
@@ -148,6 +155,11 @@ std::vector<BT<std::string>> wrapOptions(
     }
   };
 
+  if (nestedLinkerFlags == NestedLinkerFlags::PreserveAsSpelled) {
+    insertWrapped(options);
+    return result;
+  }
+
   for (std::vector<std::string>::size_type index = 0; index < options.size();
        index++) {
     if (cmHasLiteralPrefix(options[index], "LINKER:")) {
@@ -488,8 +500,9 @@ std::vector<BT<std::string>> cmGeneratorTarget::GetLinkOptions(
         // host link options must be wrapped
         std::vector<std::string> options;
         cmSystemTools::ParseUnixCommandLine(it->Value.c_str(), options);
-        auto hostOptions = wrapOptions(options, it->Backtrace, wrapperFlag,
-                                       wrapperSep, concatFlagAndArgs);
+        auto hostOptions =
+          wrapOptions(options, it->Backtrace, wrapperFlag, wrapperSep,
+                      concatFlagAndArgs, NestedLinkerFlags::Normalize);
         it = result.erase(it);
         // some compilers (like gcc 4.8 or Intel 19.0 or XLC 16) do not respect
         // C++11 standard: 'std::vector::insert()' do not returns an iterator,
@@ -538,12 +551,11 @@ std::vector<BT<std::string>>& cmGeneratorTarget::ResolveLinkerWrapper(
   const std::string SHELL{ "SHELL:" };
   const std::string LINKER_SHELL = LINKER + SHELL;
 
-  std::vector<BT<std::string>>::iterator entry;
-  while ((entry = std::find_if(result.begin(), result.end(),
-                               [&LINKER](BT<std::string> const& item) -> bool {
-                                 return item.Value.compare(0, LINKER.length(),
-                                                           LINKER) == 0;
-                               })) != result.end()) {
+  for (auto entry = result.begin(); entry != result.end(); ++entry) {
+    if (entry->Value.compare(0, LINKER.length(), LINKER) != 0) {
+      continue;
+    }
+
     std::string value = std::move(entry->Value);
     cmListFileBacktrace bt = std::move(entry->Backtrace);
     entry = result.erase(entry);
@@ -573,15 +585,19 @@ std::vector<BT<std::string>>& cmGeneratorTarget::ResolveLinkerWrapper(
       return result;
     }
 
-    std::vector<BT<std::string>> options = wrapOptions(
-      linkerOptions, bt, wrapperFlag, wrapperSep, concatFlagAndArgs);
+    // Very old versions of the C++ standard library return void for insert, so
+    // can't use it to get the new iterator
+    const auto index = entry - result.begin();
+    std::vector<BT<std::string>> options =
+      wrapOptions(linkerOptions, bt, wrapperFlag, wrapperSep,
+                  concatFlagAndArgs, NestedLinkerFlags::PreserveAsSpelled);
     if (joinItems) {
-      result.insert(entry,
-                    cmJoin(cmRange<decltype(options.cbegin())>(
-                             options.cbegin(), options.cend()),
-                           " "_s));
+      result.insert(
+        entry, cmJoin(cmMakeRange(options.begin(), options.end()), " "_s));
+      entry = std::next(result.begin(), index);
     } else {
       result.insert(entry, options.begin(), options.end());
+      entry = std::next(result.begin(), index + options.size() - 1);
     }
   }
   return result;