unix: fix symbol references for x86 Mac

1 files changed, 12 insertions, 0 deletions

diff --git a/unix/gccollect.c b/unix/gccollect.c
index 397c4ffe1..4ec8c2bf5 100644
--- a/unix/gccollect.c
+++ b/unix/gccollect.c
@@ -80,6 +80,18 @@ STATIC void gc_helper_get_regs(regs_t arr) {
     register long esi asm ("esi");
     register long edi asm ("edi");
     register long ebp asm ("ebp");
+#ifdef __clang__
+    // TODO:
+    // This is dirty workaround for Clang. It tries to get around
+    // uncompliant (wrt to GCC) behavior of handling register variables.
+    // Application of this patch here is random, and done only to unbreak
+    // MacOS build. Better, cross-arch ways to deal with Clang issues should
+    // be found.
+    asm("" : "=r"(ebx));
+    asm("" : "=r"(esi));
+    asm("" : "=r"(edi));
+    asm("" : "=r"(ebp));
+#endif
     arr[0] = ebx;
     arr[1] = esi;
     arr[2] = edi;