std: replace debug.Dwarf.ElfModule with debug.ElfFile

This abstraction isn't really tied to DWARF at all! Really, we're just
loading some information from an ELF file which is useful for debugging.
That *includes* DWARF, but it also includes other information. For
instance, the other change here:

Now, if DWARF information is missing, `debug.SelfInfo.ElfModule` will
name symbols by finding a matching symtab entry. We actually already do
this on Mach-O, so it makes obvious sense to do the same on ELF! This
change is what motivated the restructuring to begin with.

The symtab work is derived from #22077.

Co-authored-by: geemili <opensource@geemili.xyz>

1 files changed, 1 insertions, 0 deletions

diff --git a/lib/std/debug/SelfInfo.zig b/lib/std/debug/SelfInfo.zig
index ef222cc7f4..d838a1a6c1 100644
--- a/lib/std/debug/SelfInfo.zig
+++ b/lib/std/debug/SelfInfo.zig
@@ -78,6 +78,7 @@ pub fn getSymbolAtAddress(self: *SelfInfo, gpa: Allocator, address: usize) Error
 pub fn getModuleNameForAddress(self: *SelfInfo, gpa: Allocator, address: usize) Error![]const u8 {
     comptime assert(target_supported);
     const module: Module = try .lookup(&self.lookup_cache, gpa, address);
+    if (module.name.len == 0) return error.MissingDebugInfo;
     return module.name;
 }