Merge pull request #18560 from ziglang/elf-report-dupes

elf: report duplicate symbol definitions

1 files changed, 26 insertions, 0 deletions

diff --git a/src/link/Elf/ZigObject.zig b/src/link/Elf/ZigObject.zig
index a29c3ab69c..ef8509e915 100644
--- a/src/link/Elf/ZigObject.zig
+++ b/src/link/Elf/ZigObject.zig
@@ -451,6 +451,32 @@ pub fn markLive(self: *ZigObject, elf_file: *Elf) void {
     }
 }
 
+pub fn checkDuplicates(self: *ZigObject, dupes: anytype, elf_file: *Elf) error{OutOfMemory}!void {
+    for (self.globals(), 0..) |index, i| {
+        const esym = self.global_esyms.items(.elf_sym)[i];
+        const shndx = self.global_esyms.items(.shndx)[i];
+        const global = elf_file.symbol(index);
+        const global_file = global.file(elf_file) orelse continue;
+
+        if (self.index == global_file.index() or
+            esym.st_shndx == elf.SHN_UNDEF or
+            esym.st_bind() == elf.STB_WEAK or
+            esym.st_shndx == elf.SHN_COMMON) continue;
+
+        if (esym.st_shndx == SHN_ATOM) {
+            const atom_index = self.atoms.items[shndx];
+            const atom = elf_file.atom(atom_index) orelse continue;
+            if (!atom.flags.alive) continue;
+        }
+
+        const gop = try dupes.getOrPut(index);
+        if (!gop.found_existing) {
+            gop.value_ptr.* = .{};
+        }
+        try gop.value_ptr.append(elf_file.base.comp.gpa, self.index);
+    }
+}
+
 /// This is just a temporary helper function that allows us to re-read what we wrote to file into a buffer.
 /// We need this so that we can write to an archive.
 /// TODO implement writing ZigObject data directly to a buffer instead.