[compiler-rt] Reland '[hwasan] Add fixed_shadow_base flag (#73980)' (PR #95445)

[Vitaly Buka via llvm-commits]

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@@ -106,8 +106,13 @@ static uptr GetHighMemEnd() {
 }
 
 static void InitializeShadowBaseAddress(uptr shadow_size_bytes) {
-  __hwasan_shadow_memory_dynamic_address =
-      FindDynamicShadowStart(shadow_size_bytes);
+  // Android static HWASan doesn't initialize flags correctly
+  if (!SANITIZER_ANDROID && flags()->fixed_shadow_base != (uptr)-1) {
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vitalybuka wrote:

please use SANITIZER_CAN_USE_PREINIT_ARRAY
as it's the real rootcause

https://github.com/llvm/llvm-project/pull/95445