Revert "[ASan] Not linking asan_static library for DSO."

[kstoimenov]

Summary

This reverts commit cf730d8ce1341ba593144df2e2bc8411238e04c3. It turned out that D118184 is causing segfaults in some situations.

clang/lib/Driver/ToolChains/CommonArgs.cpp

if (SanArgs.needsHwasanRt() && SanArgs.linkRuntimes()) {
         SharedRuntimes.push_back("hwasan");
     }
   }
 
   // The stats_client library is also statically linked into DSOs.
   if (SanArgs.needsStatsRt() && SanArgs.linkRuntimes())
     StaticRuntimes.push_back("stats_client");
 
+  // Always link the static runtime regardless of DSO or executable.
+  if (SanArgs.needsAsanRt())
+    HelperStaticRuntimes.push_back("asan_static");
+
   // Collect static runtimes.
   if (Args.hasArg(options::OPT_shared)) {
     // Don't link static runtimes into DSOs.
     return;
   }
 
-  // Always link the static runtime for executable.
-  if (SanArgs.needsAsanRt())
-    HelperStaticRuntimes.push_back("asan_static");
-
   // Each static runtime that has a DSO counterpart above is excluded below,
   // but runtimes that exist only as static are not affected by needsSharedRt.
 
   if (!SanArgs.needsSharedRt() && SanArgs.needsAsanRt() && SanArgs.linkRuntimes()) {
     StaticRuntimes.push_back("asan");
     if (SanArgs.linkCXXRuntimes())
       StaticRuntimes.push_back("asan_cxx");
   }

clang/test/Driver/sanitizer-ld.c

 // CHECK-ASAN-EXECUTABLE-LINUX: libclang_rt.asan-x86_64
 
 // RUN: %clang -fsanitize=address -shared %s -### -o %t.o 2>&1  \
 // RUN:     -target x86_64-unknown-linux -fuse-ld=ld \
 // RUN:     -resource-dir=%S/Inputs/resource_dir \
 // RUN:     --sysroot=%S/Inputs/basic_linux_tree \
 // RUN:   | FileCheck --check-prefix=CHECK-ASAN-SHARED-LINUX %s
 //
-// CHECK-ASAN-SHARED-LINUX-NOT: libclang_rt.asan_static-x86_64
+// CHECK-ASAN-SHARED-LINUX: libclang_rt.asan_static-x86_64
 // CHECK-ASAN-SHARED-LINUX-NOT: libclang_rt.asan-x86_64
 
 // RUN: %clang -no-canonical-prefixes %s -### -o %t.o 2>&1 \
 // RUN:     -target i386-unknown-linux -fuse-ld=ld -fsanitize=address -shared-libsan \
 // RUN:     -resource-dir=%S/Inputs/resource_dir \
 // RUN:     --sysroot=%S/Inputs/basic_linux_tree \
 // RUN:   | FileCheck --check-prefix=CHECK-SHARED-ASAN-LINUX %s