fix -Wvexing-parse

Summary:
```lang=cpp
folly/test/stl_tests/StlVectorTest.cpp:1975:11: error: parentheses were disambiguated as redundant parentheses around declaration of variable named 'm' [-Werror,-Wvexing-parse]
    Vector(m);
          ^~~
folly/test/stl_tests/StlVectorTest.cpp:1975:11: note: add a variable name to declare a 'Vector' initialized with 'm'
    Vector(m);
          ^
           varname
folly/test/stl_tests/StlVectorTest.cpp:1975:5: note: add enclosing parentheses to perform a function-style cast
    Vector(m);
    ^
    (        )
folly/test/stl_tests/StlVectorTest.cpp:1975:11: note: remove parentheses to silence this warning
    Vector(m);
          ^ ~

1 error generated.
```

Reviewed By: Gownta

Differential Revision: D5955613

fbshipit-source-id: 3015570ce111603b3561914d07b55365a221c686

diff --git a/folly/test/stl_tests/StlVectorTest.cpp b/folly/test/stl_tests/StlVectorTest.cpp
index b80b8dfe2f678c45b55cc13eba4b6ee183990159..b107cd9891b2951674d59696a1b984b0e81c8e3b 100644 (file)
--- a/folly/test/stl_tests/StlVectorTest.cpp
+++ b/folly/test/stl_tests/StlVectorTest.cpp
@@ -1972,7 +1972,7 @@ STL_TEST("23.2.1 Table 99.4", customAllocator, is_destructible, m) {
   ASSERT_TRUE(u.get_allocator() == m);
 
   if (false) {
-    Vector(m);
+    Vector t(m);
   }
 }