Runtime error on ESP32 using Contract.h

I’m using Web3E with an ESP32. Standalone `Web3.h` works fine, but `Contract.h` causes problems, though.
This is what I’m trying to do:

```
queryERC20Balance(ERC20CONTRACT, MY_ADDRESS);
```

Whereas `void queryERC20Balance(const char* Address, const char* ERC20ContractAddress)` is taken from the [repo examples](https://github.com/AlphaWallet/Web3E/blob/master/examples/Query%20Token%20Balance/main.cpp):

```
void queryERC20Balance(const char* contractAddress, const char *userAddress)
{
String address = userAddress;

string param = contract.SetupContractData("balanceOf(address)", &address);
string result = contract.ViewCall(¶m);

param = contract.SetupContractData("decimals()", &address);
result = contract.ViewCall(¶m);

int decimals = web3.getInt(&result);

uint256_t baseBalance = web3.getUint256(&result);
string balanceStr = Util::ConvertWeiToEthString(&baseBalance, decimals); //use decimals to calculate value, not all ERC20 use 18 decimals

Serial.println(balanceStr.c_str());
}
```

This is the decoded backtrace:

```
Backtrace: 0x40085058:0x3ffb1ba0 0x400852d5:0x3ffb1bc0 0x400f6777:0x3ffb1be0 0x400f67be:0x3ffb1c00 0x400f5ddf:0x3ffb1c20 0x400f61de:0x3ffb1c40 0x400fc00d:0x3ffb1c60 0x400d239f:0x3ffb1c80 0x400d254b:0x3ffb1cb0 0x400d2b65:0x3ffb1d40 0x400d1a47:0x3ffb1eb0 0x400d1c92:0x3ffb1f80 0x400df282:0x3ffb1fb0 0x400862d6:0x3ffb1fd0
#0 0x40085058:0x3ffb1ba0 in invoke_abort at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/esp-idf/components/esp32/panic.c:715
#1 0x400852d5:0x3ffb1bc0 in abort at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/esp-idf/components/esp32/panic.c:715
#2 0x400f6777:0x3ffb1be0 in __cxxabiv1::__terminate(void (*)()) at /builds/idf/crosstool-NG/.build/src/gcc-5.2.0/libstdc++-v3/libsupc++/eh_terminate.cc:112
#3 0x400f67be:0x3ffb1c00 in std::terminate() at /builds/idf/crosstool-NG/.build/src/gcc-5.2.0/libstdc++-v3/libsupc++/eh_terminate.cc:112
#4 0x400f5ddf:0x3ffb1c20 in __cxa_throw at /builds/idf/crosstool-NG/.build/src/gcc-5.2.0/libstdc++-v3/libsupc++/eh_throw.cc:87
#5 0x400f61de:0x3ffb1c40 in operator new(unsigned int) at /builds/idf/crosstool-NG/.build/src/gcc-5.2.0/libstdc++-v3/libsupc++/new_op.cc:54
#6 0x400fc00d:0x3ffb1c60 in __gnu_cxx::new_allocator::allocate(unsigned int, void const*) at /builds/idf/crosstool-NG/.build/xtensa-esp32-elf/build/build-cc-gcc-final/xtensa-esp32-elf/libstdc++-v3/include/bits/basic_string.h:2200
(inlined by) std::allocator_traits >::allocate(std::allocator&, unsigned int) at /builds/idf/crosstool-NG/.build/xtensa-esp32-elf/build/build-cc-gcc-final/xtensa-esp32-elf/libstdc++-v3/include/bits/alloc_traits.h:360
(inlined by) std::__cxx11::basic_string, std::allocator >::_M_create(unsigned int&, unsigned int) at /builds/idf/crosstool-NG/.build/xtensa-esp32-elf/build/build-cc-gcc-final/xtensa-esp32-elf/libstdc++-v3/include/bits/basic_string.tcc:157
#7 0x400d239f:0x3ffb1c80 in void std::__cxx11::basic_string, std::allocator >::_M_construct(char*, char*, std::forward_iterator_tag) at /Users/keno/.platformio/packages/toolchain-xtensa32/xtensa-esp32-elf/include/c++/5.2.0/bits/basic_string.tcc:223
#8 0x400d254b:0x3ffb1cb0 in void std::__cxx11::basic_string, std::allocator >::_M_construct_aux(char*, char*, std::__false_type) at /Users/keno/.platformio/packages/toolchain-xtensa32/xtensa-esp32-elf/include/c++/5.2.0/bits/basic_string.h:195
(inlined by) void std::__cxx11::basic_string, std::allocator >::_M_construct(char*, char*) at /Users/keno/.platformio/packages/toolchain-xtensa32/xtensa-esp32-elf/include/c++/5.2.0/bits/basic_string.h:214
(inlined by) std::__cxx11::basic_string, std::allocator >::basic_string(std::__cxx11::basic_string, std::allocator > const&) at /Users/keno/.platformio/packages/toolchain-xtensa32/xtensa-esp32-elf/include/c++/5.2.0/bits/basic_string.h:401
(inlined by) Contract::GenerateBytesForAddress(std::__cxx11::basic_string, std::allocator > const*) at lib/Web3E/src/Contract.cpp:216
#9 0x400d2b65:0x3ffb1d40 in Contract::SetupContractData[abi:cxx11](char const*, ...) at lib/Web3E/src/Contract.cpp:99 (discriminator 7)
#10 0x400d1a47:0x3ffb1eb0 in queryERC20Balance(char const*, char const*) at src/main.cpp:101
#11 0x400d1c92:0x3ffb1f80 in setup() at src/main.cpp:88
#12 0x400df282:0x3ffb1fb0 in loopTask(void*) at /Users/keno/.platformio/packages/framework-arduinoespressif32/cores/esp32/main.cpp:32
#13 0x400862d6:0x3ffb1fd0 in vPortTaskWrapper at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/esp-idf/components/freertos/port.c:355 (discriminator 1)
```

Can someone help me with that, please? It seems there’s a probkem with `Contract::GenerateBytesForAddress()`, right?