Fix another case where libstdc++ is being inappropriately requested (see r328775) for all platforms.

[delcypher]

Summary

Fix another case where libstdc++ is being inappropriately requested (see
r328775) for all platforms.

Given that this is the second occurance of this problem it seemed worth
fixing this problem in a more generic way. r328775 has been reverted and
now a substitution %linux_static_libstdcplusplus has been provided.
This substitution expands to Clang driver arguments to use a static
libstdc++ on Linux and on all other platforms it expands to nothing.

The asan/TestCases/throw_invoke_test.cc and
test/tsan/static_init6.cc test cases now use this substitution.

rdar://problem/39948818

[kubamracek]

test/tsan/static_init6.cc

2

This doesn't actually call FileCheck.

[delcypher]

test/tsan/static_init6.cc

2

Nice catch. I think clang-format might be responsible for this.

[delcypher]

Fix FileCheck not being executed in test.

[kubamracek]

Thanks!

test/asan/TestCases/Linux/throw_invoke_test_libstdcxx.cc

-// This the basically the `throw_invoke_test.cc` test but using libstdc++
-// instead of the default.
-// RUN: %clangxx_asan %s -o %t -stdlib=libstdc++ -static-libstdc++ && %run %t
-
-#include <stdio.h>
-static volatile int zero = 0;
-inline void pretend_to_do_something(void *x) {
-  __asm__ __volatile__("" : : "r"(x) : "memory");
-}
-
-__attribute__((noinline)) void ReallyThrow() {
-  fprintf(stderr, "ReallyThrow\n");
-  try {
-    if (zero == 0)
-      throw 42;
-    else if (zero == 1)
-      throw 1.;
-  } catch (double x) {
-  }
-}
-
-__attribute__((noinline)) void Throw() {
-  int a, b, c, d, e;
-  pretend_to_do_something(&a);
-  pretend_to_do_something(&b);
-  pretend_to_do_something(&c);
-  pretend_to_do_something(&d);
-  pretend_to_do_something(&e);
-  fprintf(stderr, "Throw stack = %p\n", &a);
-  ReallyThrow();
-}
-
-__attribute__((noinline)) void CheckStack() {
-  int ar[100];
-  pretend_to_do_something(ar);
-  for (int i = 0; i < 100; i++)
-    ar[i] = i;
-  fprintf(stderr, "CheckStack stack = %p, %p\n", ar, ar + 100);
-}
-
-int main(int argc, char **argv) {
-  try {
-    Throw();
-  } catch (int a) {
-    fprintf(stderr, "a = %d\n", a);
-  }
-  CheckStack();
-}

test/asan/TestCases/throw_invoke_test.cc

 // RUN: %clangxx_asan %s -o %t && %run %t
+// RUN: %clangxx_asan %s -o %t %linux_static_libstdcplusplus && %run %t
 
 #include <stdio.h>
 static volatile int zero = 0;
 inline void pretend_to_do_something(void *x) {
   __asm__ __volatile__("" : : "r" (x) : "memory");
 }
 
 __attribute__((noinline))

test/lit.common.cfg

elif config.host_os == 'FreeBSD' or config.host_os == 'NetBSD':
   config.substitutions.append( ("%ld_flags_rpath_so", '') )
 elif config.host_os == 'Linux':
   config.substitutions.append( ("%ld_flags_rpath_exe", "-Wl,-rpath,\$ORIGIN -L%T -l%xdynamiclib_namespec") )
   config.substitutions.append( ("%ld_flags_rpath_so", '') )
 elif config.host_os == 'SunOS':
   config.substitutions.append( ("%ld_flags_rpath_exe", "-Wl,-R\$ORIGIN -L%T -l%xdynamiclib_namespec") )
   config.substitutions.append( ("%ld_flags_rpath_so", '') )
 
+# Provide a substituion that can be used to tell Clang to use a static libstdc++.
+# The substitution expands to nothing on non Linux platforms.
+# FIXME: This should check the target OS, not the host OS.
+if config.host_os == 'Linux':
+  config.substitutions.append( ("%linux_static_libstdcplusplus", "-stdlib=libstdc++ -static-libstdc++") )
+else:
+  config.substitutions.append( ("%linux_static_libstdcplusplus", "") )
+
 # Must be defined after the substitutions that use %dynamiclib.
 config.substitutions.append( ("%dynamiclib", '%T/%xdynamiclib_filename') )
 config.substitutions.append( ("%xdynamiclib_filename", 'lib%xdynamiclib_namespec.so') )
 config.substitutions.append( ("%xdynamiclib_namespec", '%basename_t.dynamic') )
 
 config.default_sanitizer_opts = []
 if config.host_os == 'Darwin':
   # On Darwin, we default to `abort_on_error=1`, which would make tests run

test/tsan/static_init6.cc

-// RUN: %clangxx_tsan -stdlib=libstdc++ -static-libstdc++ -O1 %s -o %t && %run %t 2>&1 | FileCheck %s
+// RUN: %clangxx_tsan %linux_static_libstdcplusplus -O1 %s -o %t && %run %t 2>&1 \
+// RUN: | FileCheck %s
 #include <pthread.h>
 #include <stdlib.h>
 #include <stdio.h>
 #include <sched.h>
 
 struct Cache {
   int x;
   explicit Cache(int x)