diff --git a/sdk/userspace/include/fpga_mgmt.h b/sdk/userspace/include/fpga_mgmt.h
index 57ad437c7..c2a66dd00 100644
--- a/sdk/userspace/include/fpga_mgmt.h
+++ b/sdk/userspace/include/fpga_mgmt.h
@@ -20,6 +20,10 @@
 #include <hal/fpga_common.h>
 #include <fpga_pci.h>
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 /**
  * Initialize the fpga_mgmt library.
  * Calls fpga_pci_init.
@@ -158,3 +162,7 @@ int fpga_mgmt_set_vDIP(int slot_id, uint16_t value);
  * @returns 0 on success, non-zero on error
  */
 int fpga_mgmt_get_vDIP_status(int slot_id, uint16_t *value);
+
+#ifdef __cplusplus
+}
+#endif
diff --git a/sdk/userspace/include/fpga_pci.h b/sdk/userspace/include/fpga_pci.h
index b36b3260e..3541dff0a 100644
--- a/sdk/userspace/include/fpga_pci.h
+++ b/sdk/userspace/include/fpga_pci.h
@@ -19,6 +19,10 @@
 
 #include <hal/fpga_common.h>
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 /**
  * FPGA_PCI_BARS_MAX:
  *  -compile time tunable via mkall_fpga_mgmt_tools.sh, with the below default.
@@ -203,3 +207,7 @@ int fpga_pci_rescan_slot_app_pfs(int slot_id);
  */
 int fpga_pci_get_address(pci_bar_handle_t handle, uint64_t offset,
 	uint64_t dword_len, void **ptr);
+
+#ifdef __cplusplus
+}
+#endif
diff --git a/sdk/userspace/include/utils/io.h b/sdk/userspace/include/utils/io.h
index b1776f1cf..b029956b1 100644
--- a/sdk/userspace/include/utils/io.h
+++ b/sdk/userspace/include/utils/io.h
@@ -23,6 +23,10 @@
 #include <stdbool.h>
 #include <sys/types.h>
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 /**
  * Set up epoll.
  *
@@ -200,3 +204,7 @@ int string_to_uint(unsigned int *num, const char *str);
  * @returns	How many files are open in a given process, -1 on error.
  */
 int number_of_open_files(pid_t pid);
+
+#ifdef __cplusplus
+}
+#endif
diff --git a/sdk/userspace/include/utils/lcd.h b/sdk/userspace/include/utils/lcd.h
index 038928cfe..006c56248 100644
--- a/sdk/userspace/include/utils/lcd.h
+++ b/sdk/userspace/include/utils/lcd.h
@@ -31,6 +31,10 @@
 /** PCI device format string */
 #define PCI_DEV_FMT "%04x:%02x:%02x.%d"
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 /**
  * Sleep for some milliseconds.
  *
@@ -42,9 +46,13 @@
 static inline int msleep(uint64_t ms)
 {
 	struct timespec sleep_time = {
-		.tv_sec = ms / MS_PER_SECOND,
-		.tv_nsec = (ms % MS_PER_SECOND) * NS_PER_MS
+		.tv_sec = (time_t)(ms / MS_PER_SECOND),
+		.tv_nsec = (long)((ms % MS_PER_SECOND) * NS_PER_MS)
 	};
 
 	return clock_nanosleep(CLOCK_MONOTONIC, 0, &sleep_time, NULL);
 }
+
+#ifdef __cplusplus
+}
+#endif
diff --git a/sdk/userspace/include/utils/log.h b/sdk/userspace/include/utils/log.h
index 60cec19aa..09149785c 100644
--- a/sdk/userspace/include/utils/log.h
+++ b/sdk/userspace/include/utils/log.h
@@ -40,6 +40,10 @@ enum {
 	LOGGER_FLAGS_SERIALIZE = (1u << 0),
 };
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 /** Logger. */
 struct logger {
 	/** Name (for debugging). */
@@ -174,3 +178,7 @@ static inline __printf(1, 2) void log_dummy(const char *fmt, ...)
 extern const struct logger logger_stdout;
 extern const struct logger logger_kmsg;
 extern const struct logger *logger_default;
+
+#ifdef __cplusplus
+}
+#endif