Assert on first thread allocation on 3.5.2
Author: sagaceiloCreated Sep 13, 2026Updated Sep 15, 2026
Hey. Just updated to 3.5.2 and it asserts about missing theap in the very first allocation on new thread.
Editor_debug.exe!_mi_assert_fail(const char * assertion, const char * fname, unsigned int line, const char * func) Line 572 C++
Editor_debug.exe!mi_theap_malloc(mi_theap_s * theap, unsigned __int64 size) Line 278 C++
Editor_debug.exe!mi_theap_alloc_new(mi_theap_s * theap, unsigned __int64 size) Line 830 C++
Editor_debug.exe!mi_new(unsigned __int64 size) Line 837 C++
Editor_debug.exe!operator new(unsigned __int64 n) Line 40 C++mi_new() -> _mi_theap_default() seems to return nullptr. 100% occurrence. 3.5.1 verified to behave correct.
Source: microsoft/mimalloc