I’ve been following the tutorial at https://github.com/cfenollosa/os-tutorial to create a custom 32-bit os on x86_64 asm and c, and i got to the screen drivers part which is about writing to the vga buffer to display characters on the screen from inside the kernel.
I prefer c++ so im using it instead of c, but now im getting this issue where if i use a char pointer to store a string instead of a int pointer i can’t get to display anything.

This is my main function, where i initialize the pointer and populate it with characters from A to L, which works if i use a int pointer, but not with a char one.

#define size 12

int main(){
    char* ptr = (char*)0x11000FF; // int* ptr = (int*)0x11000FF works
    
    for(int i = 0; i < size; i++){
        ptr[i] = 'A'+i;
    }
    ptr[size+1] = '';

    for(int i = 0; i < size; i++){
        printChar(i,0,ptr[i]);
    }
}

Here is my print function

#define VIDEO_ADDRESS 0xB8000
#define MAX_ROWS 25
#define MAX_COLS 80
#define WHITE_ON_BLACK 0x0F

#include "screen.h"

void printChar(unsigned int x, unsigned int y, char c){
    char* videoMem = (char*)VIDEO_ADDRESS;

    unsigned int offset = ((y*MAX_COLS + x)*2)+1;
    videoMem[offset] = c;
    videoMem[offset+1] = WHITE_ON_BLACK;
}

And here is my Makefile

SOURCE_DIR=source
BOOTLOADER_DIR=$(SOURCE_DIR)/bootloader
KERNEL_DIR=$(SOURCE_DIR)/kernel
BUILD_DIR=build

SRCs := $(shell find $(SOURCE_DIR) -name '*.cpp')   #List of all .cpp files
OBJS := $(patsubst $(SOURCE_DIR)/%.cpp,$(BUILD_DIR)/%.o,$(SRCs)) #List of all c++ object files

all: folder run clean #Build from zero and wipe

run: os.iso #Start VM
    qemu-system-x86_64 -drive file=$(BUILD_DIR)/$<,format=raw,index=0,media=disk

os.iso: bootloader.bin kernel.bin #Concatenate bootloader and kernel into single file
    cat $(BUILD_DIR)/bootloader.bin $(BUILD_DIR)/kernel.bin > $(BUILD_DIR)/$@

bootloader.bin: $(BOOTLOADER_DIR)/bootloader.asm #Compile bootloader
    nasm $< -f bin -o $(BUILD_DIR)/$@

kernel.bin: entry.o $(OBJS) #Link all object files
    x86_64-elf-ld -o $(BUILD_DIR)/$@ -Ttext 0x512 $(BUILD_DIR)/$< $(OBJS) --oformat binary 

entry.o: $(KERNEL_DIR)/kernelentry.asm #Compile kernel entry point
    nasm $< -f elf64 -o $(BUILD_DIR)/$@

$(BUILD_DIR)/%.o: $(SOURCE_DIR)/%.cpp #Generic for compiling .cpp files
    g++ -c $< -o $@ -fpermissive

folder: #Create build folder
    mkdir -p $(BUILD_DIR)/kernel/drivers

clean: #Wipe build folder
    rm -rf $(BUILD_DIR)/*

I would expect for these two to do the same, since they are both being casted into a char when passed into the printChar function, and data size in memory shouldn’t matter since they are being passed into it by index.