std.mem.Allocator: allow shrink to fail

closes #13535

src/codegen/c.zig

@@ -1286,7 +1286,7 @@ pub const DeclGen = struct {
         }
         try bw.writeAll(");\n");
 
-        const rendered = buffer.toOwnedSlice();
+        const rendered = try buffer.toOwnedSlice();
         errdefer dg.typedefs.allocator.free(rendered);
         const name = rendered[name_begin..name_end];
 
@@ -1326,7 +1326,7 @@ pub const DeclGen = struct {
         const name_end = buffer.items.len;
         try bw.writeAll(";\n");
 
-        const rendered = buffer.toOwnedSlice();
+        const rendered = try buffer.toOwnedSlice();
         errdefer dg.typedefs.allocator.free(rendered);
         const name = rendered[name_begin..name_end];
 
@@ -1369,7 +1369,7 @@ pub const DeclGen = struct {
         buffer.appendSliceAssumeCapacity(buffer.items[name_begin..name_end]);
         buffer.appendSliceAssumeCapacity(";\n");
 
-        const rendered = buffer.toOwnedSlice();
+        const rendered = try buffer.toOwnedSlice();
         errdefer dg.typedefs.allocator.free(rendered);
         const name = rendered[name_begin..name_end];
 
@@ -1413,7 +1413,7 @@ pub const DeclGen = struct {
         }
         try buffer.appendSlice("};\n");
 
-        const rendered = buffer.toOwnedSlice();
+        const rendered = try buffer.toOwnedSlice();
         errdefer dg.typedefs.allocator.free(rendered);
 
         try dg.typedefs.ensureUnusedCapacity(1);
@@ -1448,7 +1448,7 @@ pub const DeclGen = struct {
         try buffer.writer().print("}} zig_T_{};\n", .{typeToCIdentifier(t, dg.module)});
         const name_end = buffer.items.len - ";\n".len;
 
-        const rendered = buffer.toOwnedSlice();
+        const rendered = try buffer.toOwnedSlice();
         errdefer dg.typedefs.allocator.free(rendered);
         const name = rendered[name_begin..name_end];
 
@@ -1510,7 +1510,7 @@ pub const DeclGen = struct {
         if (t.unionTagTypeSafety()) |_| try buffer.appendSlice(" } payload;\n");
         try buffer.appendSlice("};\n");
 
-        const rendered = buffer.toOwnedSlice();
+        const rendered = try buffer.toOwnedSlice();
         errdefer dg.typedefs.allocator.free(rendered);
 
         try dg.typedefs.ensureUnusedCapacity(1);
@@ -1553,7 +1553,7 @@ pub const DeclGen = struct {
         const name_end = buffer.items.len;
         try bw.writeAll(";\n");
 
-        const rendered = buffer.toOwnedSlice();
+        const rendered = try buffer.toOwnedSlice();
         errdefer dg.typedefs.allocator.free(rendered);
         const name = rendered[name_begin..name_end];
 
@@ -1586,7 +1586,7 @@ pub const DeclGen = struct {
         const c_len_val = Value.initPayload(&c_len_pl.base);
         try bw.print("[{}];\n", .{try dg.fmtIntLiteral(Type.usize, c_len_val)});
 
-        const rendered = buffer.toOwnedSlice();
+        const rendered = try buffer.toOwnedSlice();
         errdefer dg.typedefs.allocator.free(rendered);
         const name = rendered[name_begin..name_end];
 
@@ -1614,7 +1614,7 @@ pub const DeclGen = struct {
         const name_end = buffer.items.len;
         try bw.writeAll(";\n");
 
-        const rendered = buffer.toOwnedSlice();
+        const rendered = try buffer.toOwnedSlice();
         errdefer dg.typedefs.allocator.free(rendered);
         const name = rendered[name_begin..name_end];
 
@@ -1643,7 +1643,7 @@ pub const DeclGen = struct {
         const name_end = buffer.items.len;
         try buffer.appendSlice(";\n");
 
-        const rendered = buffer.toOwnedSlice();
+        const rendered = try buffer.toOwnedSlice();
         errdefer dg.typedefs.allocator.free(rendered);
         const name = rendered[name_begin..name_end];
 
@@ -2006,7 +2006,7 @@ pub const DeclGen = struct {
         _ = try airBreakpoint(bw);
         try buffer.appendSlice("}\n");
 
-        const rendered = buffer.toOwnedSlice();
+        const rendered = try buffer.toOwnedSlice();
         errdefer dg.typedefs.allocator.free(rendered);
         const name = rendered[name_begin..name_end];
 
@@ -2108,7 +2108,7 @@ pub const DeclGen = struct {
         dg.module.markDeclAlive(decl);
 
         if (dg.module.decl_exports.get(decl_index)) |exports| {
-            return writer.writeAll(exports[0].options.name);
+            return writer.writeAll(exports.items[0].options.name);
         } else if (decl.isExtern()) {
             return writer.writeAll(mem.sliceTo(decl.name, 0));
         } else {

src/codegen/llvm.zig

@@ -693,7 +693,7 @@ pub const Object = struct {
         for (mod.decl_exports.values()) |export_list, i| {
             const decl_index = export_keys[i];
             const llvm_global = object.decl_map.get(decl_index) orelse continue;
-            for (export_list) |exp| {
+            for (export_list.items) |exp| {
                 // Detect if the LLVM global has already been created as an extern. In such
                 // case, we need to replace all uses of it with this exported global.
                 // TODO update std.builtin.ExportOptions to have the name be a
@@ -1215,8 +1215,7 @@ pub const Object = struct {
             else => |e| return e,
         };
 
-        const decl_exports = module.decl_exports.get(decl_index) orelse &[0]*Module.Export{};
-        try o.updateDeclExports(module, decl_index, decl_exports);
+        try o.updateDeclExports(module, decl_index, module.getDeclExports(decl_index));
     }
 
     pub fn updateDecl(self: *Object, module: *Module, decl_index: Module.Decl.Index) !void {
@@ -1239,8 +1238,7 @@ pub const Object = struct {
             },
             else => |e| return e,
         };
-        const decl_exports = module.decl_exports.get(decl_index) orelse &[0]*Module.Export{};
-        try self.updateDeclExports(module, decl_index, decl_exports);
+        try self.updateDeclExports(module, decl_index, module.getDeclExports(decl_index));
     }
 
     /// TODO replace this with a call to `Module::getNamedValue`. This will require adding