[Bug 55623] New: The 32-bit imm32:imm32 gets a stack overflow in UTF-8 locales

[WineHQ Bugzilla]

https://bugs.winehq.org/show_bug.cgi?id=55623

Bug ID: 55623
           Summary: The 32-bit imm32:imm32 gets a stack overflow in UTF-8
                    locales
           Product: Wine
           Version: unspecified
          Hardware: x86-64
                OS: Windows
            Status: NEW
          Severity: normal
          Priority: P2
         Component: imm32
          Assignee: [e-mail]
          Reporter: [e-mail]

The 32-bit imm32:imm32 gets a stack overflow in UTF-8 locales:

imm32:imm32 start dlls/imm32/tests/imm32.c
imm32:imm32:17c4 done (-1073740791) in 2s 0B

See https://test.winehq.org/data/patterns.html#imm32:imm32

Where -1073740791 == 0xC0000409 == STATUS_STACK_BUFFER_OVERRUN

This crash is systematic and specific to the combination of the 32-bit test and
UTF-8 locales:
* w10pro64_hi       + 32-bit -> success
* w10pro64_hi       + 64-bit -> success
* w10pro64_hi_u8    + 32-bit -> crash
* w10pro64_hi_u8    + 64-bit -> success
* w10pro64_en_AE_u8 + 32-bit -> crash
* w10pro64_en_AE_u8 + 64-bit -> success

The traces indicate that the crash happens between ImmUnlockIMC() and return
TRUE in ime_ImeSelect():

ImmUnlockIMC( himc );
    }

return TRUE;

ime_ImeSelect() gets called during test_ImmSetCompositionFont(FALSE):

ok_ret( 1, ImmActivateLayout( hkl ) );