4 files changed, 29 insertions, 15 deletions

diff --git a/src/main/cpp/blaze.cc b/src/main/cpp/blaze.cc
index a17f86d0de..afb701d787 100644
--- a/src/main/cpp/blaze.cc
+++ b/src/main/cpp/blaze.cc
@@ -829,8 +829,9 @@ static int ForwardServerOutput(int socket, int output) {
     }
 
     remaining -= bytes;
-    // Not much we can do if this doesn't work
-    write(output, server_output_buffer, bytes);
+    if (write(output, server_output_buffer, bytes) != bytes) {
+      // Not much we can do if this doesn't work, just placate the compiler.
+    }
   }
 
   return 0;
@@ -1454,7 +1455,9 @@ static void sigprintf(const char *format, ...) {
   va_start(ap, format);
   int r = vsnprintf(buf, sizeof buf, format, ap);
   va_end(ap);
-  write(STDERR_FILENO, buf, r);
+  if (write(STDERR_FILENO, buf, r) <= 0) {
+    // We don't care, just placate the compiler.
+  }
 }
 
 // Signal handler.
@@ -2111,13 +2114,17 @@ unsigned int GrpcBlazeServer::Communicate() {
     }
 
     if (response.standard_output().size() > 0) {
-      write(1, response.standard_output().c_str(),
-            response.standard_output().size());
+      if (write(1, response.standard_output().c_str(),
+                response.standard_output().size()) <= 0) {
+        // Placate the compiler.
+      }
     }
 
     if (response.standard_error().size() > 0) {
-      write(2, response.standard_error().c_str(),
-            response.standard_error().size());
+      if (write(2, response.standard_error().c_str(),
+            response.standard_error().size()) <= 0) {
+        // Placate the compiler.
+      }
     }
 
     if (!command_id_set && response.command_id().size() > 0) {
@@ -2150,7 +2157,9 @@ void GrpcBlazeServer::Disconnect() {
 
 void GrpcBlazeServer::SendAction(CancelThreadAction action) {
   char msg = action;
-  write(send_socket_, &msg, 1);  // We assume this always works
+  if (write(send_socket_, &msg, 1) <= 0) {
+    // We assume this always works, just placate the compiler.
+  }
 }
 
 void GrpcBlazeServer::Cancel() {
diff --git a/src/main/cpp/blaze_util.cc b/src/main/cpp/blaze_util.cc
index 0c5ced094c..3c5bdabe15 100644
--- a/src/main/cpp/blaze_util.cc
+++ b/src/main/cpp/blaze_util.cc
@@ -411,13 +411,16 @@ uint64_t AcquireLock(const string& output_base, bool batch_mode, bool block,
   }
 
   // Identify ourselves in the lockfile.
-  ftruncate(lockfd, 0);
+  if (ftruncate(lockfd, 0)) {
+    // Placate the compiler.
+  }
   const char *tty = ttyname(STDIN_FILENO);  // NOLINT (single-threaded)
   string msg = "owner=launcher\npid="
       + ToString(getpid()) + "\ntty=" + (tty ? tty : "") + "\n";
-  // Don't bother checking for error, since it's unlikely and unimportant.
   // The contents are currently meant only for debugging.
-  write(lockfd, msg.data(), msg.size());
+  if (write(lockfd, msg.data(), msg.size()) <= 0) {
+    // Placate the compiler.
+  }
   blaze_lock->lockfd = lockfd;
   return wait_time;
 }
diff --git a/src/main/cpp/blaze_util_posix.cc b/src/main/cpp/blaze_util_posix.cc
index 12498c4f9a..2203cb0b20 100644
--- a/src/main/cpp/blaze_util_posix.cc
+++ b/src/main/cpp/blaze_util_posix.cc
@@ -100,7 +100,9 @@ static void Daemonize(const string& daemon_output) {
     // In a daemon, no-one can hear you scream.
     open("/dev/null", O_WRONLY);
   }
-  dup(STDOUT_FILENO);  // stderr (2>&1)
+  if (dup(STDOUT_FILENO)) {  // stderr (2>&1)
+    // Placate the compiler.
+  }
 }
 
 class PipeBlazeServerStartup : public BlazeServerStartup {
@@ -200,6 +202,7 @@ string RunProgram(const string& exe, const std::vector<string>& args_vector) {
     ExecuteProgram(exe, args_vector);
     pdie(blaze_exit_code::INTERNAL_ERROR, "Failed to run %s", exe.c_str());
   }
+  return string("");  //  We cannot reach here, just placate the compiler.
 }
 
 bool ReadDirectorySymlink(const string &name, string* result) {
diff --git a/src/main/cpp/util/md5.cc b/src/main/cpp/util/md5.cc
index 05d2ba276c..d25c292787 100644
--- a/src/main/cpp/util/md5.cc
+++ b/src/main/cpp/util/md5.cc
@@ -156,9 +156,8 @@ void Md5Digest::Finish(unsigned char digest[16]) {
 
   /* Put the 64-bit file length in *bits* at the end of the buffer.  */
   unsigned int size = (ctx_buffer_len < 56 ? 64 : 128);
-  *(reinterpret_cast<uint32_t*>(ctx_buffer + size - 8)) = count[0] << 3;
-  *(reinterpret_cast<uint32_t*>(ctx_buffer + size - 4)) =
-      (count[1] << 3) | (count[0] >> 29);
+  uint32_t words[2] = { count[0] << 3, (count[1] << 3) | (count[0] >> 29) };
+  memcpy(ctx_buffer + size - 8, words, 8);
 
   memcpy(ctx_buffer + ctx_buffer_len, kPadding, size - 8 - ctx_buffer_len);