2 files changed, 20 insertions, 6 deletions
diff --git a/src/commonlib/bsd/include/commonlib/bsd/compiler.h b/src/commonlib/bsd/include/commonlib/bsd/compiler.h
index 42f9235e8e..aada973749 100644
--- a/src/commonlib/bsd/include/commonlib/bsd/compiler.h
+++ b/src/commonlib/bsd/include/commonlib/bsd/compiler.h
@@ -15,8 +15,21 @@
 #define __aligned(x) __attribute__((__aligned__(x)))
 #endif
 
-#ifndef __unused
-#define __unused __attribute__((__unused__))
+/* Because there may be variables/parameters whose name contains "__unused" in
+   header files of libc, namely musl, these names consistent with ones in the
+   Linux kernel may be a better choice. */
+
+/* This is used to mark identifiers unused in all conditions, e.g. a parameter
+   completely unused in all code branch, only present to fit an API. */
+#ifndef __always_unused
+#define __always_unused __attribute__((__unused__))
+#endif
+
+/* This is used to mark identifiers unused in some conditions, e.g. a parameter
+   only unused in some code branches, a global variable only accessed with code
+   being conditionally preprocessed, etc. */
+#ifndef __maybe_unused
+#define __maybe_unused __attribute__((__unused__))
 #endif
 
 #ifndef __must_check
diff --git a/src/commonlib/region.c b/src/commonlib/region.c
index 04c3180754..252f6faf12 100644
--- a/src/commonlib/region.c
+++ b/src/commonlib/region.c
@@ -222,7 +222,7 @@ void xlate_window_init(struct xlate_window *window, const struct region_device *
 }
 
 static void *mdev_mmap(const struct region_device *rd, size_t offset,
-			size_t size __unused)
+			size_t size __always_unused)
 {
 	const struct mem_region_device *mdev;
 
@@ -231,8 +231,8 @@ static void *mdev_mmap(const struct region_device *rd, size_t offset,
 	return &mdev->base[offset];
 }
 
-static int mdev_munmap(const struct region_device *rd __unused,
-			void *mapping __unused)
+static int mdev_munmap(const struct region_device *rd __always_unused,
+			void *mapping __always_unused)
 {
 	return 0;
 }
@@ -368,7 +368,8 @@ static void *xlate_mmap(const struct region_device *rd, size_t offset,
 	return rdev_mmap(xlwindow->access_dev, offset, size);
 }
 
-static int xlate_munmap(const struct region_device *rd __unused, void *mapping __unused)
+static int xlate_munmap(const struct region_device *rd __always_unused,
+			void *mapping __always_unused)
 {
 	/*
 	 * xlate_region_device does not keep track of the access device that was used to service