Fix FreeBSD build

This restores some CPP'd code that was added in
c18911602e and accidentally lost in
2477e4e3b8.

Co-authored-by: Eelco Dolstra <edolstra@gmail.com>

configure.ac

@@ -369,6 +369,14 @@ if test "$gc" = yes; then
   PKG_CHECK_MODULES([BDW_GC], [bdw-gc])
   CXXFLAGS="$BDW_GC_CFLAGS $CXXFLAGS"
   AC_DEFINE(HAVE_BOEHMGC, 1, [Whether to use the Boehm garbage collector.])
+
+  # See `fixupBoehmStackPointer`, for the integration between Boehm GC
+  # and Boost coroutines.
+  old_CFLAGS="$CFLAGS"
+  # Temporary set `-pthread` just for the next check
+  CFLAGS="$CFLAGS -pthread"
+  AC_CHECK_FUNCS([pthread_attr_get_np pthread_getattr_np])
+  CFLAGS="$old_CFLAGS"
 fi
 
 AS_IF([test "$ENABLE_UNIT_TESTS" == "yes"],[

src/libexpr/eval.cc

@@ -48,6 +48,9 @@
 #define GC_INCLUDE_NEW
 
 #include <pthread.h>
+#if __FreeBSD__
+#  include <pthread_np.h>
+#endif
 
 #include <gc/gc.h>
 #include <gc/gc_cpp.h>
@@ -264,23 +267,35 @@ static BoehmGCStackAllocator boehmGCStackAllocator;
  * However, the implementation is quite lean, and usually we don't have active
  * coroutines during evaluation, so this is acceptable.
  */
-void fixupBoehmStackPointer(void ** sp_ptr, void * pthread_id) {
+void fixupBoehmStackPointer(void ** sp_ptr, void * _pthread_id) {
     void *& sp = *sp_ptr;
+    auto pthread_id = reinterpret_cast<pthread_t>(_pthread_id);
     pthread_attr_t pattr;
     size_t osStackSize;
     void * osStackLow;
     void * osStackBase;
 
 #  ifdef __APPLE__
-    osStackSize = pthread_get_stacksize_np((pthread_t)pthread_id);
-    osStackLow = pthread_get_stackaddr_np((pthread_t)pthread_id);
+    osStackSize = pthread_get_stacksize_np(pthread_id);
+    osStackLow = pthread_get_stackaddr_np(pthread_id);
 #  else
     if (pthread_attr_init(&pattr)) {
         throw Error("fixupBoehmStackPointer: pthread_attr_init failed");
     }
-    if (pthread_getattr_np((pthread_t)pthread_id, &pattr)) {
+#    ifdef HAVE_PTHREAD_GETATTR_NP
+    if (pthread_getattr_np(pthread_id, &pattr)) {
         throw Error("fixupBoehmStackPointer: pthread_getattr_np failed");
     }
+#    elif HAVE_PTHREAD_ATTR_GET_NP
+    if (!pthread_attr_init(&pattr)) {
+        throw Error("fixupBoehmStackPointer: pthread_attr_init failed");
+    }
+    if (!pthread_attr_get_np(pthread_id, &pattr)) {
+        throw Error("fixupBoehmStackPointer: pthread_attr_get_np failed");
+    }
+#    else
+#      error "Need one of `pthread_attr_get_np` or `pthread_getattr_np`"
+#    endif
     if (pthread_attr_getstack(&pattr, &osStackLow, &osStackSize)) {
         throw Error("fixupBoehmStackPointer: pthread_attr_getstack failed");
     }

src/libstore/build/derivation-goal.cc

@@ -25,6 +25,10 @@
 #include <fcntl.h>
 #include <unistd.h>
 
+#ifndef _WIN32 // TODO abstract over proc exit status
+# include <sys/wait.h>
+#endif
+
 #include <nlohmann/json.hpp>
 
 namespace nix {
@@ -1033,7 +1037,7 @@ void DerivationGoal::buildDone()
 
         BuildResult::Status st = BuildResult::MiscFailure;
 
-#ifndef _WIN32
+#ifndef _WIN32 // TODO abstract over proc exit status
         if (hook && WIFEXITED(status) && WEXITSTATUS(status) == 101)
             st = BuildResult::TimedOut;
 

tests/unit/libstore/worker-protocol.cc

@@ -1,4 +1,5 @@
 #include <regex>
+#include <thread>
 
 #include <nlohmann/json.hpp>
 #include <gtest/gtest.h>