WIN64: 'Access violation reading location 0x0000000000000000' and 'Debug Assertion Failed! ... Expression: _CrtIsValidHeapPointer(block)' qlarl runtime errors for static builds using MSVC

Hello, everyone,

For builds using MSVC got error during 'qlarl.exe' run:

configure -v -opensource -confirm-license -debug -static -platform win32-msvc -c++std c++11 -static-runtime -icu ICU_PREFIX="%CD%\..\..\libICU-62.0-dev\MSVC64DT" -opengl dynamic && jom

<snip>

The thread 0x1a18 has exited with code 0 (0x0).
Unhandled exception at 0x00007FF7D362FF33 in qlalr.exe: 0xC0000005: Access violation reading location 0x0000000000000000.

which appeared after moving from

Qt5-dev-7dbaf0c6516a09df6d80c519d313ec43d32e60de builds with ICU-60.2

to

Qt5-dev-60dd5ad4519bf7f988c6c8641004b0acb173077b builds with ICU-62.0-dev.

Reproduced for:

• static builds using Windows ICC and MSVC with static ICU binaries,

not reproduced for:

• shared builds using Windows ICC and MSVC with shared ICU binaries,
• builds using mingw-w64.

After some investigations found, that for builds using MSVC without ICU there is similar error during 'qlarl.exe' run:

configure -v -opensource -confirm-license -debug -static -platform win32-msvc -static-runtime -opengl dynamic && jom

<snip>

Debug Assertion Failed!

Program: C:\libQT-5.12-dev\build\qtbase\bin\qlalr.exe
File: minkernel\crts\ucrt\src\appcrt\heap\debug_heap.cpp
Line: 604

Expression: _CrtIsValidHeapPointer(block)

For information on how your program can cause an assertion
failure, see the Visual C++ documentation on asserts.

(Press Retry to debug the application)

which was introduced by Change #177245.

Reproduced for:

• debug static builds using Windows ICC and MSVC,

not reproduced for:

• debug static builds using Windows ICC and MSVC with QtBase sources reset before Change #177245,
• release static builds using Windows ICC and MSVC,
• builds using mingw-w64.

Assuming both errors relate to the same source and fixing none-ICU builds would affect ICU builds too.

CC: owolff, buddenha, kkohne.

Best,

Alexander