From 65e234adfd91f5bfba8cbf3f14f1a9507cfd035d Mon Sep 17 00:00:00 2001
From: Shawn Landden <shawn@git.icu>
Date: Wed, 27 Mar 2019 01:10:45 +0000
Subject: [PATCH] fix build on arm64

---
 src/codegen.cpp           | 10 ++--------
 src/compiler.cpp          | 11 ++++++-----
 src/os.cpp                | 18 ++++++++++++++++++
 src/os.hpp                |  8 ++++++++
 std/special/bootstrap.zig |  7 +++++++
 5 files changed, 41 insertions(+), 13 deletions(-)

diff --git a/src/codegen.cpp b/src/codegen.cpp
index 015680b5d..8de3e8119 100644
--- a/src/codegen.cpp
+++ b/src/codegen.cpp
@@ -7989,15 +7989,9 @@ static void detect_dynamic_linker(CodeGen *g) {
 #if defined(ZIG_OS_LINUX)
         {
             Error err;
-            static const char *dyn_tests[] = {
-#if defined(ZIG_ARCH_X86_64)
-                "ld-linux-x86-64.so.2",
-                "ld-musl-x86_64.so.1",
-#endif
-            };
             Buf *result = buf_alloc();
-            for (size_t i = 0; i < array_length(dyn_tests); i += 1) {
-                const char *lib_name = dyn_tests[i];
+            for (size_t i = 0; possible_ld_names[i] != NULL; i += 1) {
+                const char *lib_name = possible_ld_names[i];
                 if ((err = zig_libc_cc_print_file_name(lib_name, result, false, true))) {
                     if (err != ErrorCCompilerCannotFindFile) {
                         fprintf(stderr, "Unable to detect native dynamic linker: %s\n", err_str(err));
diff --git a/src/compiler.cpp b/src/compiler.cpp
index 7ec1485fa..af62173db 100644
--- a/src/compiler.cpp
+++ b/src/compiler.cpp
@@ -26,11 +26,12 @@ Buf *get_stage1_cache_path(void) {
 }
 
 static void detect_dynamic_linker(Buf *lib_path) {
-#if defined(ZIG_OS_LINUX) && defined(ZIG_ARCH_X86_64)
-    if (buf_ends_with_str(lib_path, "ld-linux-x86-64.so.2")) {
-        buf_init_from_buf(&saved_dynamic_linker_path, lib_path);
-    } else if (buf_ends_with_str(lib_path, "ld-musl-x86-64.so.1")) {
-        buf_init_from_buf(&saved_dynamic_linker_path, lib_path);
+#if defined(ZIG_OS_LINUX)
+    for (size_t i = 0; possible_ld_names[i] != NULL; i += 1) {
+        if (buf_ends_with_str(lib_path, possible_ld_names[i])) {
+            buf_init_from_buf(&saved_dynamic_linker_path, lib_path);
+            break;
+        }
     }
 #endif
 }
diff --git a/src/os.cpp b/src/os.cpp
index 4f7ca74f2..1dd22b718 100644
--- a/src/os.cpp
+++ b/src/os.cpp
@@ -2076,3 +2076,21 @@ void os_file_close(OsFile file) {
     close(file);
 #endif
 }
+
+#ifdef ZIG_OS_LINUX
+const char *possible_ld_names[] = {
+#if defined(ZIG_ARCH_X86_64)
+    "ld-linux-x86-64.so.2",
+    "ld-musl-x86_64.so.1",
+#elif defined(ZIG_ARCH_ARM64)
+    "ld-linux-aarch64.so.1",
+    "ld-musl-aarch64.so.1",
+#elif defined(ZIG_ARCH_ARM)
+    "ld-linux-armhf.so.3",
+    "ld-musl-armhf.so.1",
+    "ld-linux.so.3",
+    "ld-musl-arm.so.1",
+#endif
+    NULL,
+};
+#endif
diff --git a/src/os.hpp b/src/os.hpp
index 36d3c327a..c9fc26e60 100644
--- a/src/os.hpp
+++ b/src/os.hpp
@@ -33,10 +33,18 @@
 
 #if defined(__x86_64__)
 #define ZIG_ARCH_X86_64
+#elif defined(__aarch64__)
+#define ZIG_ARCH_ARM64
+#elif defined(__arm__)
+#define ZIG_ARCH_ARM
 #else
 #define ZIG_ARCH_UNKNOWN
 #endif
 
+#ifdef ZIG_OS_LINUX
+extern const char *possible_ld_names[];
+#endif
+
 #if defined(ZIG_OS_WINDOWS)
 #define ZIG_PRI_usize "I64u"
 #define ZIG_PRI_u64 "I64u"
diff --git a/std/special/bootstrap.zig b/std/special/bootstrap.zig
index 04b29d670..064d8bac6 100644
--- a/std/special/bootstrap.zig
+++ b/std/special/bootstrap.zig
@@ -171,6 +171,13 @@ fn linuxSetThreadArea(addr: usize) void {
             // acrh_prctl is documented to never fail
             assert(rc == 0);
         },
+        builtin.Arch.aarch64 => {
+            asm volatile (
+                \\        msr tpidr_el0,x0
+                \\        mov w0,#0
+                \\        ret
+            );
+        },
         else => @compileError("Unsupported architecture"),
     }
 }