Created attachment 3741 [details]
Proposed patch

Hello,
I tried to use SDL2 with sanitizers enabled and found a few lines of code with the same bug: left-shifting Uint8 by 24 bits; integer promotion rule promotes Uint8 to int and therefore shifting yields signed integer overflow.

Steps to reproduce: add -fsanitize=address,undefined when building SDL2.
Compile the sample program:

#include <SDL.h>

int main(int argc, char** argv) {
    SDL_Init(SDL_INIT_EVERYTHING);
    SDL_Window* win = SDL_CreateWindow("window", SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED, 800, 600, 0);
    SDL_Renderer* ren = SDL_CreateRenderer(win, -1, 0);

    SDL_SetRenderDrawColor(ren, 0xff, 0xff, 0xff, 0xff);
    SDL_RenderClear(ren);
    SDL_RenderPresent(ren);

    SDL_DestroyRenderer(ren);
    SDL_DestroyWindow(win);
    SDL_Quit();
}

Expected Results: The application exits normally.

Actual results: The pplication crashes with SIGILL:
[1]    15110 illegal hardware instruction (core dumped)  ./sdl2-il
#0  0x0000555555822355 in GL_RunCommandQueue (renderer=0x6160000e6180, cmd=0x6040000566d0, vertices=0x0, vertsize=0)
    at /home/sergey/dev/test/sdl2-il/build/_deps/sdl2-src/src/render/opengl/SDL_render_gl.c:1145
#1  0x000055555579c90e in FlushRenderCommands (renderer=0x6160000e6180) at /home/sergey/dev/test/sdl2-il/build/_deps/sdl2-src/src/render/SDL_render.c:215
#2  0x00005555557ed136 in SDL_RenderPresent_REAL (renderer=0x6160000e6180) at /home/sergey/dev/test/sdl2-il/build/_deps/sdl2-src/src/render/SDL_render.c:3078
#3  0x000055555572e501 in SDL_RenderPresent (a=0x6160000e6180) at /home/sergey/dev/test/sdl2-il/build/_deps/sdl2-src/src/dynapi/SDL_dynapi_procs.h:377
#4  0x0000555555726f30 in main(int, char**) (argc=1, argv=0x7fffffffe188) at /home/sergey/dev/test/sdl2-il/main.cpp:9

Found problems (rev 0ff5bbe35bf5):
src/render/SDL_render.c
src/render/opengl/SDL_render_gl.c
src/render/opengles/SDL_render_gles.c
src/render/opengles2/SDL_render_gles2.c
src/render/psp/SDL_render_psp.c
src/video/x11/edid-parse.c (?)

Proposed patch attached.