merge gnu function and data sections (#327)

Author: codeshaunted

objdiff-core/src/obj/read.rs

@@ -874,8 +874,12 @@ fn combine_sections(
     let mut data_sections = BTreeMap::<String, Vec<usize>>::new();
     let mut text_sections = BTreeMap::<String, Vec<usize>>::new();
     for (i, section) in sections.iter().enumerate() {
-        let base_name =
-            if let Some(i) = section.name.rfind('$') { &section.name[..i] } else { &section.name };
+        let base_name = section
+            .name
+            .get(1..)
+            .and_then(|s| s.rfind(['$', '.']))
+            .and_then(|i| section.name.get(..i + 1))
+            .unwrap_or(&section.name);
         match section.kind {
             SectionKind::Data | SectionKind::Bss => {
                 data_sections.entry(base_name.to_string()).or_default().push(i);