expose both basename(3) on Linux with glibc

libc-test/build.rs

@@ -3417,6 +3417,22 @@ fn test_linux(target: &str) {
             // it can't be changed from struct.
             "pthread_sigqueue" => true,
 
+            // There are two versions of basename(3) on Linux with glibc, see
+            //
+            // https://man7.org/linux/man-pages/man3/basename.3.html
+            //
+            // If libgen.h is included, then the POSIX version will be available;
+            // If _GNU_SOURCE is defined and string.h is included, then the GNU one
+            // will be used.
+            //
+            // libc exposes both of them, providing a prefix to differentiate between
+            // them.
+            //
+            // Because the name with prefix is not a valid symbol in C, we have to
+            // skip the tests.
+            "posix_basename" if gnu => true,
+            "gnu_basename" if gnu => true,
+
             _ => false,
         }
     });

libc-test/semver/linux-gnu.txt

@@ -659,4 +659,5 @@ ctime_r
 strftime
 strptime
 dirname
-basename
+posix_basename
+gnu_basename

src/unix/linux_like/linux/gnu/mod.rs

@@ -1348,7 +1348,12 @@ extern "C" {
     pub fn strptime(s: *const ::c_char, format: *const ::c_char, tm: *mut ::tm) -> *mut ::c_char;
 
     pub fn dirname(path: *mut ::c_char) -> *mut ::c_char;
-    pub fn basename(path: *mut ::c_char) -> *mut ::c_char;
+    /// POSIX version of `basename(3)`, defined in `libgen.h`.
+    #[link_name = "__xpg_basename"]
+    pub fn posix_basename(path: *mut ::c_char) -> *mut ::c_char;
+    /// GNU version of `basename(3)`, defined in `string.h`.
+    #[link_name = "basename"]
+    pub fn gnu_basename(path: *const ::c_char) -> *mut ::c_char;
 }
 
 extern "C" {