[clang] [FreeBSD] Support -stdlib=libstdc++ (PR #126302)

[Jessica Clarke via cfe-commits]

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@@ -452,12 +452,12 @@ void FreeBSD::addLibCxxIncludePaths(const llvm::opt::ArgList &DriverArgs,
 
 void FreeBSD::AddCXXStdlibLibArgs(const ArgList &Args,
                                   ArgStringList &CmdArgs) const {
+  Generic_ELF::AddCXXStdlibLibArgs(Args, CmdArgs);
   unsigned Major = getTriple().getOSMajorVersion();
-  bool Profiling = Args.hasArg(options::OPT_pg) && Major != 0 && Major < 14;
-
-  CmdArgs.push_back(Profiling ? "-lc++_p" : "-lc++");
-  if (Args.hasArg(options::OPT_fexperimental_library))
-    CmdArgs.push_back("-lc++experimental");
+  bool SuffixedLib = Args.hasArg(options::OPT_pg) && Major != 0 && Major < 14;
+  if (SuffixedLib && GetCXXStdlibType(Args) == CST_Libcxx)
+    llvm::replace(CmdArgs, static_cast<const char *>("-lc++"),
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jrtc27 wrote:

Given how simple the base AddCXXStdlibLibArgs is, should we not just reimplement the other bits here rather than do this slightly gross replacement? That's what all the other implementations seem to do.

https://github.com/llvm/llvm-project/pull/126302