Commit 0c355bef9e424fbf06085f12fc28979d73b3d6af | zig

author	LemonBoy <thatlemon@gmail.com> 2020-10-18 21:54:24+02:00
committer	Andrew Kelley <andrew@ziglang.org> 2020-10-21 23:35:06-04:00
log	0c355bef9e424fbf06085f12fc28979d73b3d6af
tree	b7ccd34b0ce21c303ed3fb69fa2f17e10efc9a0e
parent	1e074879046354db1b556fc9eda51bc8dac5c6b7

std: Slim down the error code path in initStaticTLS

Calling @panic made the executable ~30x times bigger, use a simple
`abort()` and let the user figure out what went wrong.

Supporting ARMv6 (and earlier?) platforms is not a priority.

Closes #6676

1 files changed, 10 insertions(+), 6 deletions(-)

lib
- std
  - os
    linux
    tls.zig

lib/std/os/linux/tls.zig+10-6

 @@ -211,12 +211,16 @@ fn initTLS() void {
         }
     }
-    // If the cpu is ARM-based, check if it supports the TLS register
+    // ARMv6 targets (and earlier) have no support for TLS in hardware
-    if (comptime builtin.arch.isARM() and at_hwcap & std.os.linux.HWCAP_TLS == 0) {
+    // FIXME: Elide the check for targets >= ARMv7 when the target feature API
-        // If the CPU does not support TLS via a coprocessor register,
+    // becomes less verbose (and more usable).
-        // a kernel helper function can be used instead on certain linux kernels.
+    if (comptime builtin.arch.isARM()) {
-        // See linux/arch/arm/include/asm/tls.h and musl/src/thread/arm/__set_thread_area.c.
+        if (at_hwcap & std.os.linux.HWCAP_TLS == 0) {
-        @panic("TODO: Implement ARM fallback TLS functionality");
+            // FIXME: Make __aeabi_read_tp call the kernel helper kuser_get_tls
+            // For the time being use a simple abort instead of a @panic call to
+            // keep the binary bloat under control.
+            std.os.abort();
+        }
     }
     var tls_align_factor: usize = undefined;