Add additional tests in an attempt to diagnose ARM test failures.

Currently 4 tests are failing on the ARM buildbot. To try and diagnose each
of the failures this patch does the following:

1) path.itr/iterator.pass.cpp
   * Temporarily print iteration sequence to see where its failing.

2) path.native.obs/string_alloc.pass.cpp
   * Remove test that ::new is not called when constructing a short string
     that requires a conversion. Since during the conversion global locale
     objects might be constructed.

3) fs.op.funcs/space.pass.cpp
   * Explicitly use uintmax_t in the implementation of space, hopefully
     preventing possible overflows.
   * Add additional tests that check for overflow is the calculation of the
     space_info values.
   * Add additional tests for the values returned from statfvs.

4) fs.op.funcs/last_write_time.pass.cpp
   * No changes made yet.


git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@273075 91177308-0d34-0410-b5e6-96231b3b80d8

src/experimental/filesystem/operations.cpp

@@ -669,7 +669,7 @@ void __resize_file(const path& p, std::uintmax_t size, std::error_code *ec) {
 
 space_info __space(const path& p, std::error_code *ec) {
     space_info si;
-    struct statvfs m_svfs;
+    struct statvfs m_svfs = {};
     if (::statvfs(p.c_str(), &m_svfs) == -1)  {
         set_or_throw(ec, "space", p);
         si.capacity = si.free = si.available =
@@ -678,7 +678,7 @@ space_info __space(const path& p, std::error_code *ec) {
     }
     if (ec) ec->clear();
     // Multiply with overflow checking.
-    auto do_mult = [&](std::uintmax_t& out, fsblkcnt_t other) {
+    auto do_mult = [&](std::uintmax_t& out, std::uintmax_t other) {
       out = other * m_svfs.f_frsize;
       if (out / other != m_svfs.f_frsize || other == 0)
           out = static_cast<std::uintmax_t>(-1);

test/std/experimental/filesystem/class.path/path.itr/iterator.pass.cpp

@@ -24,6 +24,8 @@
 #include <type_traits>
 #include <cassert>
 
+#include <iostream>
+
 #include "test_macros.h"
 #include "filesystem_test_helper.hpp"
 
@@ -36,6 +38,29 @@ std::reverse_iterator<It> mkRev(It it) {
 }
 
 
+template <class Iter1, class Iter2>
+bool checkCollectionsEqualVerbose(
+    Iter1 start1, Iter1 const end1
+  , Iter2 start2, Iter2 const end2
+  )
+{
+    while (start1 != end1 && start2 != end2) {
+      std::cout << "Got start1 = " << *start1 << "\n"
+                << "Got start2 = " << *start2 << "\n";
+        if (*start1 != *start2) {
+            return false;
+        }
+        ++start1; ++start2;
+    }
+  if (start1 != end1) {
+    std::cout << "Got start1 = " << *start1 << " but expected end1\n";
+  }
+  if (start2 != end2) {
+    std::cout << "Got start2 = " << *start2 << " but expected end2\n";
+  }
+    return (start1 == end1 && start2 == end2);
+}
+
 void checkIteratorConcepts() {
   using namespace fs;
   using It = path::iterator;
@@ -87,14 +112,18 @@ void checkBeginEndBasic() {
     path p("//root_name//first_dir////second_dir");
     const path expect[] = {"//root_name", "/", "first_dir", "second_dir"};
     assert(checkCollectionsEqual(p.begin(), p.end(), std::begin(expect), std::end(expect)));
-    assert(checkCollectionsEqual(mkRev(p.end()), mkRev(p.begin()), mkRev(std::end(expect)), mkRev(std::begin(expect))));
+    assert(checkCollectionsEqualVerbose(mkRev(p.end()), mkRev(p.begin()),
+                                 mkRev(std::end(expect)),
+                                 mkRev(std::begin(expect))));
   }
   {
     path p("////foo/bar/baz///");
     const path expect[] = {"/", "foo", "bar", "baz", "."};
     assert(checkCollectionsEqual(p.begin(), p.end(), std::begin(expect), std::end(expect)));
-    assert(checkCollectionsEqual(mkRev(p.end()), mkRev(p.begin()), mkRev(std::end(expect)), mkRev(std::begin(expect))));
+    assert(checkCollectionsEqual(mkRev(p.end()), mkRev(p.begin()),
+                                 mkRev(std::end(expect)), mkRev(std::begin(expect))));
   }
+
 }
 
 int main() {

test/std/experimental/filesystem/class.path/path.member/path.native.obs/string_alloc.pass.cpp

@@ -27,7 +27,6 @@
 #include "count_new.hpp"
 #include "min_allocator.h"
 #include "filesystem_test_helper.hpp"
-#include "assert_checkpoint.h"
 
 namespace fs = std::experimental::filesystem;
 
@@ -43,14 +42,37 @@ void doShortStringTest(MultiStringType const& MS) {
   Ptr value = MS;
   const path p((const char*)MS);
   {
-      DisableAllocationGuard g; // should not allocate
-      CHECKPOINT("short string default constructed allocator");
+      DisableAllocationGuard g;
+      if (!std::is_same<CharT, char>::value)
+          g.release();
       Str s = p.string<CharT>();
       assert(s == value);
-      CHECKPOINT("short string provided allocator");
       Str s2 = p.string<CharT>(Alloc{});
       assert(s2 == value);
   }
+  using MAlloc = malloc_allocator<CharT>;
+  MAlloc::reset();
+  {
+      using Traits = std::char_traits<CharT>;
+      using AStr = std::basic_string<CharT, Traits, MAlloc>;
+      AStr s = p.string<CharT, Traits, MAlloc>();
+      assert(s == value);
+      assert(MAlloc::alloc_count == 0);
+      assert(MAlloc::outstanding_alloc() == 0);
+  }
+  MAlloc::reset();
+  { // Other allocator - provided copy
+      using Traits = std::char_traits<CharT>;
+      using AStr = std::basic_string<CharT, Traits, MAlloc>;
+      MAlloc a;
+      // don't allow another allocator to be default constructed.
+      MAlloc::disable_default_constructor = true;
+      AStr s = p.string<CharT, Traits, MAlloc>(a);
+      assert(s == value);
+      assert(MAlloc::alloc_count == 0);
+      assert(MAlloc::outstanding_alloc() == 0);
+  }
+  MAlloc::reset();
 }
 
 template <class CharT>
@@ -62,7 +84,6 @@ void doLongStringTest(MultiStringType const& MS) {
   const path p((const char*)MS);
   { // Default allocator
       using Alloc = std::allocator<CharT>;
-      RequireAllocationGuard g;
       Str s = p.string<CharT>();
       assert(s == value);
       Str s2 = p.string<CharT>(Alloc{});
@@ -70,22 +91,18 @@ void doLongStringTest(MultiStringType const& MS) {
   }
   using MAlloc = malloc_allocator<CharT>;
   MAlloc::reset();
-  CHECKPOINT("Malloc allocator test - default construct");
   { // Other allocator - default construct
       using Traits = std::char_traits<CharT>;
       using AStr = std::basic_string<CharT, Traits, MAlloc>;
-      DisableAllocationGuard g;
       AStr s = p.string<CharT, Traits, MAlloc>();
       assert(s == value);
       assert(MAlloc::alloc_count > 0);
       assert(MAlloc::outstanding_alloc() == 1);
   }
   MAlloc::reset();
-  CHECKPOINT("Malloc allocator test - provided copy");
   { // Other allocator - provided copy
       using Traits = std::char_traits<CharT>;
       using AStr = std::basic_string<CharT, Traits, MAlloc>;
-      DisableAllocationGuard g;
       MAlloc a;
       // don't allow another allocator to be default constructed.
       MAlloc::disable_default_constructor = true;

test/std/experimental/filesystem/fs.op.funcs/fs.op.space/space.pass.cpp

@@ -88,6 +88,8 @@ TEST_CASE(basic_space_test)
     TEST_CHECK(expect.f_bfree > 0);
     TEST_CHECK(expect.f_bsize > 0);
     TEST_CHECK(expect.f_blocks > 0);
+    TEST_CHECK(expect.f_frsize > 0);
+    const std::uintmax_t bad_value = static_cast<std::uintmax_t>(-1);
     const std::uintmax_t expect_cap = expect.f_blocks * expect.f_frsize;
     // Other processes running on the operating system may have changed
     // the amount of space available. Check that these are within tolerances.
@@ -101,11 +103,14 @@ TEST_CASE(basic_space_test)
         StaticEnv::SymlinkToDir
     };
     for (auto& p : cases) {
-        std::error_code ec = std::make_error_code(std::errc::address_in_use);
+        std::error_code ec = GetTestEC();
         space_info info = space(p, ec);
         TEST_CHECK(!ec);
+        TEST_CHECK(info.capacity != bad_value);
         TEST_CHECK((expect.f_blocks * expect.f_frsize) == info.capacity);
+        TEST_CHECK(info.free != bad_value);
         TEST_CHECK(EqualDelta((expect.f_bfree  * expect.f_frsize), info.free, delta));
+        TEST_CHECK(info.available != bad_value);
         TEST_CHECK(EqualDelta((expect.f_bavail * expect.f_frsize), info.available, delta));
     }
 }