FreeBSD build fix, adding proper dependency on backtrace too. (#1557)

Summary: Pull Request resolved: https://github.com/facebook/folly/pull/1557

Differential Revision: D27701865

Pulled By: yfeldblum

fbshipit-source-id: f9ed96a8e9283a30f1f96d15b4b8166ade5d3321

CMake/folly-deps.cmake

@@ -159,6 +159,9 @@ list(APPEND FOLLY_INCLUDE_DIRECTORIES ${LIBUNWIND_INCLUDE_DIRS})
 if (LIBUNWIND_FOUND)
   set(FOLLY_HAVE_LIBUNWIND ON)
 endif()
+if (CMAKE_SYSTEM_NAME MATCHES "FreeBSD")
+  list(APPEND FOLLY_LINK_LIBRARIES "execinfo")
+endif ()
 
 cmake_push_check_state()
 set(CMAKE_REQUIRED_DEFINITIONS -D_XOPEN_SOURCE)

folly/detail/AtFork.h

@@ -16,6 +16,8 @@
 
 #pragma once
 
+#include <sys/types.h>
+
 #include <folly/Function.h>
 
 namespace folly {

folly/experimental/symbolizer/Dwarf.cpp

@@ -1317,9 +1317,11 @@ Dwarf::LineNumberVM::StepResult Dwarf::LineNumberVM::step(
       // use unbounded amounts of state (ie. use the heap).  We'll do a second
       // pass (using nextDefineFile()) if necessary.
       break;
+#if !defined(__FreeBSD__)
     case DW_LNE_set_discriminator:
       discriminator_ = readULEB(program);
       return CONTINUE;
+#endif
   }
 
   // Unrecognized extended opcode

folly/experimental/symbolizer/Elf.h

@@ -41,7 +41,7 @@ namespace symbolizer {
 #if defined(ElfW)
 #define FOLLY_ELF_ELFW(name) ElfW(name)
 #elif defined(__FreeBSD__)
-#define FOLLY_ELF_ELFW(...) Elf_##name
+#define FOLLY_ELF_ELFW(name) Elf_##name
 #endif
 
 using ElfAddr = FOLLY_ELF_ELFW(Addr);

folly/memory/detail/MallocImpl.h

@@ -38,9 +38,9 @@ int mallctlnametomib(const char*, size_t*, size_t*)
     __attribute__((__nothrow__, __weak__));
 int mallctlbymib(const size_t*, size_t, void*, size_t*, void*, size_t)
     __attribute__((__nothrow__, __weak__));
+#endif
 bool MallocExtension_Internal_GetNumericProperty(const char*, size_t, size_t*)
     __attribute__((__weak__));
-#endif
 #else
 #if (!defined(USE_JEMALLOC) && !defined(FOLLY_USE_JEMALLOC)) || FOLLY_SANITIZE
 // we do not want to declare these if we have jemalloc support

folly/portability/Stdlib.h

@@ -55,7 +55,7 @@ char*** _NSGetEnviron(void);
 
 #if defined(__FreeBSD__)
 // Needed to resolve linkage
-char** environ;
+extern char** environ;
 #endif
 
 #if !__linux__ && !FOLLY_MOBILE