Fix two files with different extensions having the same object name (#1295)

Author: NobodyXu

src/command_helpers.rs

@@ -327,6 +327,9 @@ pub(crate) fn objects_from_files(files: &[Arc<Path>], dst: &Path) -> Result<Vec<
         };
 
         hasher.write(dirname.as_bytes());
+        if let Some(extension) = file.extension() {
+            hasher.write(extension.to_string_lossy().as_bytes());
+        }
         let obj = dst
             .join(format!("{:016x}-{}", hasher.finish(), basename))
             .with_extension("o");

tests/test.rs

@@ -27,7 +27,7 @@ fn gnu_smoke() {
         .must_have("-ffunction-sections")
         .must_have("-fdata-sections");
     test.cmd(1)
-        .must_have(test.td.path().join("d1fba762150c532c-foo.o"));
+        .must_have(test.td.path().join("db3b6bfb95261072-foo.o"));
 }
 
 #[test]
@@ -434,7 +434,7 @@ fn msvc_smoke() {
         .must_have("-c")
         .must_have("-MD");
     test.cmd(1)
-        .must_have(test.td.path().join("d1fba762150c532c-foo.o"));
+        .must_have(test.td.path().join("db3b6bfb95261072-foo.o"));
 }
 
 #[test]