From: Fangrui Song <maskray@google.com>
Date: Sun, 14 Jul 2019 06:46:46 +0000 (+0000)
Subject: [Driver] Simplify -lgcc & -lgcc_s
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=05629895331165f6f6024553c8d2e00de3f15fdf;p=clang

[Driver] Simplify -lgcc & -lgcc_s

gcc defaults to -shared-libgcc in C++ mode.
Letting getLibGccType() return SharedLibGcc simplifies the logic.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@366012 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Driver/ToolChains/CommonArgs.cpp b/lib/Driver/ToolChains/CommonArgs.cpp
index d0c9d7d396..b6a0afd7e5 100644
--- a/lib/Driver/ToolChains/CommonArgs.cpp
+++ b/lib/Driver/ToolChains/CommonArgs.cpp
@@ -1135,16 +1135,12 @@ bool tools::isObjCAutoRefCount(const ArgList &Args) {
 
 enum class LibGccType { UnspecifiedLibGcc, StaticLibGcc, SharedLibGcc };
 
-static LibGccType getLibGccType(const ArgList &Args) {
-  bool Static = Args.hasArg(options::OPT_static_libgcc) ||
-                Args.hasArg(options::OPT_static) ||
-                Args.hasArg(options::OPT_static_pie);
-
-  bool Shared = Args.hasArg(options::OPT_shared_libgcc);
-  if (Shared)
-    return LibGccType::SharedLibGcc;
-  if (Static)
+static LibGccType getLibGccType(const Driver &D, const ArgList &Args) {
+  if (Args.hasArg(options::OPT_static_libgcc) ||
+      Args.hasArg(options::OPT_static) || Args.hasArg(options::OPT_static_pie))
     return LibGccType::StaticLibGcc;
+  if (Args.hasArg(options::OPT_shared_libgcc) || D.CCCIsCXX())
+    return LibGccType::SharedLibGcc;
   return LibGccType::UnspecifiedLibGcc;
 }
 
@@ -1170,8 +1166,8 @@ static void AddUnwindLibrary(const ToolChain &TC, const Driver &D,
       UNW == ToolChain::UNW_None)
     return;
 
-  LibGccType LGT = getLibGccType(Args);
-  bool AsNeeded = D.CCCIsCC() && LGT == LibGccType::UnspecifiedLibGcc &&
+  LibGccType LGT = getLibGccType(D, Args);
+  bool AsNeeded = LGT == LibGccType::UnspecifiedLibGcc &&
                   !TC.getTriple().isAndroid() && !TC.getTriple().isOSCygMing();
   if (AsNeeded)
     CmdArgs.push_back("--as-needed");
@@ -1180,11 +1176,11 @@ static void AddUnwindLibrary(const ToolChain &TC, const Driver &D,
   case ToolChain::UNW_None:
     return;
   case ToolChain::UNW_Libgcc: {
-    LibGccType LGT = getLibGccType(Args);
-    if (LGT == LibGccType::UnspecifiedLibGcc || LGT == LibGccType::SharedLibGcc)
-      CmdArgs.push_back("-lgcc_s");
-    else if (LGT == LibGccType::StaticLibGcc)
+    LibGccType LGT = getLibGccType(D, Args);
+    if (LGT == LibGccType::StaticLibGcc)
       CmdArgs.push_back("-lgcc_eh");
+    else
+      CmdArgs.push_back("-lgcc_s");
     break;
   }
   case ToolChain::UNW_CompilerRT:
@@ -1200,7 +1196,7 @@ static void AddLibgcc(const ToolChain &TC, const Driver &D,
                       ArgStringList &CmdArgs, const ArgList &Args) {
   bool isAndroid = TC.getTriple().isAndroid();
 
-  LibGccType LGT = getLibGccType(Args);
+  LibGccType LGT = getLibGccType(D, Args);
   bool LibGccFirst = (D.CCCIsCC() && LGT == LibGccType::UnspecifiedLibGcc) ||
                      LGT == LibGccType::StaticLibGcc;
   if (LibGccFirst)
@@ -1216,7 +1212,7 @@ static void AddLibgcc(const ToolChain &TC, const Driver &D,
   //
   // NOTE: This fixes a link error on Android MIPS as well.  The non-static
   // libgcc for MIPS relies on _Unwind_Find_FDE and dl_iterate_phdr from libdl.
-  if (isAndroid && getLibGccType(Args) != LibGccType::StaticLibGcc)
+  if (isAndroid && getLibGccType(D, Args) != LibGccType::StaticLibGcc)
     CmdArgs.push_back("-ldl");
 }