Fix a number of c++ build errors (#715)

* Move -fvisibility-inlines-hidden from common_flags to cxx_flags

This option isn't supported by C (and causes the build to fail under
at least rodete).

Manifested error was:

```
-- Looking for include file openssl/rand.h
-- Looking for include file openssl/rand.h - not found
CMake Error at core/src/firebase/firestore/util/CMakeLists.txt:94 (message):
  No implementation for SecureRandom available.

-- Configuring incomplete, errors occurred!
```

which is completely misleading. :(

* Fix exception include for std::logic_error

Was causing compiler error on (at least) rodete.

(http://en.cppreference.com/w/cpp/error/logic_error suggests that
stdexcept is the correct header.)

* Remove 'const' from vector contents.

vectors cannot contain const objects as the contained objects are
required to be assignable and copy constructable. (Not *quite* strictly
true; since c++11, this requirement now depends on the operations
performed on the container. But my compiler objects at any rate.)

http://en.cppreference.com/w/cpp/container/vector

https://stackoverflow.com/questions/8685257/why-cant-you-put-a-const-object-into-a-stl-container

* Add brackets as suggested (required) by my compiler.

* Add missing include

For LLONG_MIN, etc.

* Enable gnu extension to c++11 for firestore/util *test*.

We disable them by default (in cmake/CompilerSetup.cmake) but our tests
requires hexidecimal floating point, which is not supported in c++11
(though is supported in C++17, gnu++11, and others).

http://en.cppreference.com/w/cpp/language/floating_literal
https://bugzilla.redhat.com/show_bug.cgi?id=1321986

* Fix printf format for uint64_t

http://en.cppreference.com/w/cpp/types/integer
https://stackoverflow.com/questions/9225567/how-to-print-a-int64-t-type-in-c

* Allow 0 length printf template strings in tests.

* Get rid of a multi line comment.

The backslash is apparently interpreted by the compiler cause the next
line to be ignored too. In this case, the next line is (currently) a
comment, and would be ignored anyways. (But that doesn't stop the
compiler from yelling.)

* Run ./scripts/style.sh

1 files changed, 5 insertions, 1 deletions

diff --git a/cmake/CompilerSetup.cmake b/cmake/CompilerSetup.cmake
index 8bcfa76..d026f82 100644
--- a/cmake/CompilerSetup.cmake
+++ b/cmake/CompilerSetup.cmake
@@ -41,6 +41,10 @@ if(CLANG OR GNU)
 
     # Delete unused things
     -Wunused-function -Wunused-value -Wunused-variable
+  )
+
+  set(
+    cxx_flags
 
     # Cut down on symbol clutter
     # TODO(wilhuff) try -fvisibility=hidden
@@ -64,7 +68,7 @@ if(CLANG OR GNU)
     set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${flag}")
   endforeach()
 
-  foreach(flag ${common_flags})
+  foreach(flag ${common_flags} ${cxx_flags})
     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${flag}")
   endforeach()
 endif()