Elf2: implement virtual allocation

This allows segments to be moved around in the output file without
needing to reapply relocations until virtual address space is exhaused.

Author: jacobly0

CMakeLists.txt

@@ -561,6 +561,7 @@ set(ZIG_STAGE2_SOURCES
     src/libs/libunwind.zig
     src/link.zig
     src/link/C.zig
+    src/link/Coff.zig
     src/link/Dwarf.zig
     src/link/Elf.zig
     src/link/Elf/Archive.zig

src/Compilation.zig

@@ -2718,35 +2718,17 @@ pub fn destroy(comp: *Compilation) void {
         }
         comp.crt_files.deinit(gpa);
     }
-
-    if (comp.libunwind_static_lib) |*crt_file| {
-        crt_file.deinit(gpa);
-    }
-    if (comp.libcxx_static_lib) |*crt_file| {
-        crt_file.deinit(gpa);
-    }
-    if (comp.libcxxabi_static_lib) |*crt_file| {
-        crt_file.deinit(gpa);
-    }
-    if (comp.compiler_rt_lib) |*crt_file| {
-        crt_file.deinit(gpa);
-    }
-    if (comp.compiler_rt_obj) |*crt_file| {
-        crt_file.deinit(gpa);
-    }
-    if (comp.ubsan_rt_lib) |*crt_file| {
-        crt_file.deinit(gpa);
-    }
-    if (comp.ubsan_rt_obj) |*crt_file| {
-        crt_file.deinit(gpa);
-    }
-    if (comp.fuzzer_lib) |*crt_file| {
-        crt_file.deinit(gpa);
-    }
-
-    if (comp.zigc_static_lib) |*crt_file| {
-        crt_file.deinit(gpa);
-    }
+    if (comp.libcxx_static_lib) |*crt_file| crt_file.deinit(gpa);
+    if (comp.libcxxabi_static_lib) |*crt_file| crt_file.deinit(gpa);
+    if (comp.libunwind_static_lib) |*crt_file| crt_file.deinit(gpa);
+    if (comp.tsan_lib) |*crt_file| crt_file.deinit(gpa);
+    if (comp.ubsan_rt_lib) |*crt_file| crt_file.deinit(gpa);
+    if (comp.ubsan_rt_obj) |*crt_file| crt_file.deinit(gpa);
+    if (comp.zigc_static_lib) |*crt_file| crt_file.deinit(gpa);
+    if (comp.compiler_rt_lib) |*crt_file| crt_file.deinit(gpa);
+    if (comp.compiler_rt_obj) |*crt_file| crt_file.deinit(gpa);
+    if (comp.compiler_rt_dyn_lib) |*crt_file| crt_file.deinit(gpa);
+    if (comp.fuzzer_lib) |*crt_file| crt_file.deinit(gpa);
 
     if (comp.glibc_so_files) |*glibc_file| {
         glibc_file.deinit(gpa);

src/link.zig

@@ -1265,7 +1265,7 @@ pub const File = struct {
 
     pub const Lld = @import("link/Lld.zig");
     pub const C = @import("link/C.zig");
-    pub const Coff2 = @import("link/Coff2.zig");
+    pub const Coff2 = @import("link/Coff.zig");
     pub const Elf = @import("link/Elf.zig");
     pub const Elf2 = @import("link/Elf2.zig");
     pub const MachO = @import("link/MachO.zig");