From 15c59f3974b3701cf48e766da1ff1bd391cbddb4 Mon Sep 17 00:00:00 2001
From: Yuri Kunde Schlesner <yuriks@yuriks.net>
Date: Tue, 21 Oct 2014 16:07:39 -0200
Subject: [PATCH] Only check OpenGL shader log if size is >1.

This prevents a crash when the buffer size returned by the driver is 0,
in which case no space is allocated to store even the NULL byte and
glGetShaderInfoLog errors out.

Thanks to @Relys for the bug report.
---
 src/video_core/renderer_opengl/gl_shader_util.cpp | 15 ++++++---------
 1 file changed, 6 insertions(+), 9 deletions(-)

diff --git a/src/video_core/renderer_opengl/gl_shader_util.cpp b/src/video_core/renderer_opengl/gl_shader_util.cpp
index 10239c8a7..a0eb0418c 100644
--- a/src/video_core/renderer_opengl/gl_shader_util.cpp
+++ b/src/video_core/renderer_opengl/gl_shader_util.cpp
@@ -29,10 +29,9 @@ GLuint LoadShaders(const char* vertex_shader, const char* fragment_shader) {
     glGetShaderiv(vertex_shader_id, GL_COMPILE_STATUS, &result);
     glGetShaderiv(vertex_shader_id, GL_INFO_LOG_LENGTH, &info_log_length);
 
-    std::vector<char> vertex_shader_error(info_log_length);
-    glGetShaderInfoLog(vertex_shader_id, info_log_length, NULL, &vertex_shader_error[0]);
-
     if (info_log_length > 1) {
+        std::vector<char> vertex_shader_error(info_log_length);
+        glGetShaderInfoLog(vertex_shader_id, info_log_length, NULL, &vertex_shader_error[0]);
         DEBUG_LOG(GPU, "%s", &vertex_shader_error[0]);
     }
 
@@ -46,10 +45,9 @@ GLuint LoadShaders(const char* vertex_shader, const char* fragment_shader) {
     glGetShaderiv(fragment_shader_id, GL_COMPILE_STATUS, &result);
     glGetShaderiv(fragment_shader_id, GL_INFO_LOG_LENGTH, &info_log_length);
 
-    std::vector<char> fragment_shader_error(info_log_length);
-    glGetShaderInfoLog(fragment_shader_id, info_log_length, NULL, &fragment_shader_error[0]);
-
     if (info_log_length > 1) {
+        std::vector<char> fragment_shader_error(info_log_length);
+        glGetShaderInfoLog(fragment_shader_id, info_log_length, NULL, &fragment_shader_error[0]);
         DEBUG_LOG(GPU, "%s", &fragment_shader_error[0]);
     }
 
@@ -65,10 +63,9 @@ GLuint LoadShaders(const char* vertex_shader, const char* fragment_shader) {
     glGetProgramiv(program_id, GL_LINK_STATUS, &result);
     glGetProgramiv(program_id, GL_INFO_LOG_LENGTH, &info_log_length);
 
-    std::vector<char> program_error(std::max(info_log_length, int(1)));
-    glGetProgramInfoLog(program_id, info_log_length, NULL, &program_error[0]);
-
     if (info_log_length > 1) {
+        std::vector<char> program_error(info_log_length);
+        glGetProgramInfoLog(program_id, info_log_length, NULL, &program_error[0]);
         DEBUG_LOG(GPU, "%s", &program_error[0]);
     }