diff --git a/gum/backend-linux/gumprocess-linux.c b/gum/backend-linux/gumprocess-linux.c
index 7b1cd7b4f..5abb649b2 100644
--- a/gum/backend-linux/gumprocess-linux.c
+++ b/gum/backend-linux/gumprocess-linux.c
@@ -49,6 +49,7 @@
 # include <sys/user.h>
 #endif
 #ifdef HAVE_LINUX
+#include <sys/time.h>
 #include <sys/resource.h>
 #endif
 
diff --git a/gum/backend-windows/gumprocess-windows.c b/gum/backend-windows/gumprocess-windows.c
index a4197ef4d..c5d926c33 100644
--- a/gum/backend-windows/gumprocess-windows.c
+++ b/gum/backend-windows/gumprocess-windows.c
@@ -643,7 +643,7 @@ gum_thread_resume (GumThreadId thread_id,
 guint64
 gum_thead_get_user_time (void)
 {
-  static gboolean initialized = false;
+  static gboolean initialized = FALSE;
   static GetThreadTimesFunc get_thread_times = NULL;
 
   HMODULE mod;
@@ -668,7 +668,7 @@ gum_thead_get_user_time (void)
   if (!get_thread_times (GetCurrentThread (), NULL, NULL, NULL, &userTime))
     return 0;
 
-  result = ((guint64) userTime.dwHighDateTime) << 32 + userTime.dwLowDateTime;
+  result = (((guint64) userTime.dwHighDateTime) << 32) + userTime.dwLowDateTime;
 
   /* Timings on Windows are to 100-nanosecond granularity. Convert to u-secs */
   return result / 10;