Why does glGetProgramInfoLog return an empty string? - c++

Question

I'm working off a code base that I know compiles correctly. Currently, I've introduced a purposeful spelling mistake into my shader to simulate an error. At this point, the code refuses to compile. I can then call
glGetShaderiv(shader, GL_INFO_LOG_LENGTH, &params);
to find that params is now 108 where is was previously 0, so I know that there is a log associated with this shader (which I have tried to compile). However, when I call
glGetProgramInfoLog(shader, 512, &size, ErrorLog);
size returns 0, and ErrorLog is still empty.
Here's the important code in this situation:
void Shader::AddShader(GLuint ShaderProgram, const char* pShaderText, GLenum ShaderType)
{
GLuint ShaderObj = glCreateShader(ShaderType);
if (ShaderObj == 0) {
fprintf(stderr, "Error creating shader type %d\n", ShaderType);
exit(1);
}
const char* pShaderSource = readShaderSource(pShaderText);
glShaderSource(ShaderObj, 1, (const GLchar**)&pShaderSource, NULL);
glCompileShader(ShaderObj);
checkCompileError(ShaderObj, ShaderType);
glAttachShader(ShaderProgram, ShaderObj);
}
bool Shader::checkCompileError(GLuint shader, GLenum ShaderType)
{
GLint params = -1;
GLchar ErrorLog[512] = { 0 };
GLint size = 0;
glGetShaderiv(shader, GL_COMPILE_STATUS, &params);
if (GL_TRUE != params) {
glGetShaderiv(shader, GL_INFO_LOG_LENGTH, &params);
glGetProgramInfoLog(shader, 512, &size, ErrorLog);
fprintf(stderr, "Error compiling shader type %d: '%s'\n", ShaderType, ErrorLog);
exit(1);
}
return true;
}

Answer 1

glGetShaderiv(shader, GL_INFO_LOG_LENGTH, &params);
glGetProgramInfoLog(shader, 512, &size, ErrorLog);
^^^^^^^ should be Shader
You're compiling & checking a shader so you should use glGetShaderInfoLog().
glGetProgramInfoLog() is for grabbing the link log of the complete shader program object you get from glCreateProgram()