Fix MacOS build issues.

PiperOrigin-RevId: 927452229

centipede/runner_dl_info.cc

diff --git a/centipede/runner_dl_info.cc b/centipede/runner_dl_info.cc
index 6d06a1b..95e2286 100644
--- a/centipede/runner_dl_info.cc
+++ b/centipede/runner_dl_info.cc
@@ -30,6 +30,7 @@
 #include <cstring>
 
 #ifdef __APPLE__
+#include <algorithm>
 #include <functional>
 #endif  // __APPLE__
 

centipede/runner_fork_server.cc

diff --git a/centipede/runner_fork_server.cc b/centipede/runner_fork_server.cc
index afd7bc2..6f67717 100644
--- a/centipede/runner_fork_server.cc
+++ b/centipede/runner_fork_server.cc
@@ -212,37 +212,40 @@
   struct sigaction sigusr1_act{};
   sigusr1_act.sa_handler = [](int) {};
 
+  // On MacOS, sigaddset() and sigemptyset() will always return 0 and cause
+  // clang to complain about unreachable code unless 0 is surrounded with extra
+  // parentheses to indicate it is "dead" code.
   sigset_t server_sigset;
   if (sigprocmask(SIG_SETMASK, nullptr, &server_sigset) != 0) {
     Exit("###sigprocmask() failed to get the existing sigset\n");
   }
-  if (sigaddset(&server_sigset, SIGINT) != 0) {
+  if (sigaddset(&server_sigset, SIGINT) != (0)) {
     Exit("###sigaddset() failed to add SIGINT\n");
   }
-  if (sigaddset(&server_sigset, SIGTERM) != 0) {
+  if (sigaddset(&server_sigset, SIGTERM) != (0)) {
     Exit("###sigaddset() failed to add SIGTERM\n");
   }
-  if (sigaddset(&server_sigset, SIGCHLD) != 0) {
+  if (sigaddset(&server_sigset, SIGCHLD) != (0)) {
     Exit("###sigaddset() failed to add SIGCHLD\n");
   }
-  if (sigaddset(&server_sigset, SIGUSR1) != 0) {
+  if (sigaddset(&server_sigset, SIGUSR1) != (0)) {
     Exit("###sigaddset() failed to add SIGUSR1\n");
   }
 
   sigset_t wait_sigset;
-  if (sigemptyset(&wait_sigset) != 0) {
+  if (sigemptyset(&wait_sigset) != (0)) {
     Exit("###sigemptyset() failed\n");
   }
-  if (sigaddset(&wait_sigset, SIGINT) != 0) {
+  if (sigaddset(&wait_sigset, SIGINT) != (0)) {
     Exit("###sigaddset() failed to add SIGINT to the wait sigset\n");
   }
-  if (sigaddset(&wait_sigset, SIGTERM) != 0) {
+  if (sigaddset(&wait_sigset, SIGTERM) != (0)) {
     Exit("###sigaddset() failed to add SIGTERM to the wait sigset\n");
   }
-  if (sigaddset(&wait_sigset, SIGCHLD) != 0) {
+  if (sigaddset(&wait_sigset, SIGCHLD) != (0)) {
     Exit("###sigaddset() failed to add SIGCHLD to the wait sigset\n");
   }
-  if (sigaddset(&wait_sigset, SIGUSR1) != 0) {
+  if (sigaddset(&wait_sigset, SIGUSR1) != (0)) {
     Exit("###sigaddset() failed to add SIGUSR1 to the wait sigset\n");
   }
 

fuzztest/internal/centipede_adaptor.cc

diff --git a/fuzztest/internal/centipede_adaptor.cc b/fuzztest/internal/centipede_adaptor.cc
index c507eb2..bc505a6 100644
--- a/fuzztest/internal/centipede_adaptor.cc
+++ b/fuzztest/internal/centipede_adaptor.cc
@@ -135,7 +135,7 @@
                          start_pos - current_argv_pos);
     ++start_pos;
   }
-  return result;
+  return results;
 #elif defined(__linux__)
   const int fd = open("/proc/self/cmdline", O_RDONLY);
   if (fd < 0) {