fix build error due to gcc 10

refer to: https://www.linuxfromscratch.org/patches/blfs/svn/freeglut-3.2.1-gcc10_fix-1.patch

freeglut.spec

@@ -1,11 +1,12 @@
 Name:           freeglut
 Version:        3.0.0
-Release:        10
+Release:        11
 Summary:        A freely licensed alternative to the GLUT library
 License:        MIT
 URL:            http://freeglut.sourceforge.net
 Source0:        https://downloads.sourceforge.net/%{name}/%{name}-%{version}.tar.gz
 Source1:        https://downloads.sourceforge.net/openglut/openglut-0.6.3-doc.tar.gz
+Patch0:         gcc-10.patch
 
 BuildRequires:  gcc gcc-c++ cmake libXi-devel libICE-devel
 BuildRequires:  pkgconfig libGLU-devel libXext-devel libXxf86vm-devel
@@ -66,5 +67,8 @@ install -p -m 644 doc/man/*.3 $RPM_BUILD_ROOT/%{_mandir}/man3
 %doc README doc/*.png doc/*.html
 
 %changelog
+* Fri Jul 30 2021 linjiaxin5 <linjiaxin5@huawei.com> - 3.0.0-11
+- Fix failure caused by GCC upgrade to 10
+
 * Fri Nov 22 2019 sunguoshuai <sunguoshuai@huawei.com> - 3.0.0-10
 - Package init.

gcc-10.patch

@@ -0,0 +1,45 @@
+--- a/src/fg_gl2.c
++++ b/src/fg_gl2.c
+@@ -26,6 +26,20 @@
+ #include <GL/freeglut.h>
+ #include "fg_internal.h"
+ #include "fg_gl2.h"
++
++#ifndef GL_ES_VERSION_2_0
++/* GLES2 has the corresponding entry points built-in, and these fgh-prefixed
++ * names are defined in fg_gl2.h header to reference them, for any other case,
++ * define them as function pointers here.
++ */
++FGH_PFNGLGENBUFFERSPROC fghGenBuffers;
++FGH_PFNGLDELETEBUFFERSPROC fghDeleteBuffers;
++FGH_PFNGLBINDBUFFERPROC fghBindBuffer;
++FGH_PFNGLBUFFERDATAPROC fghBufferData;
++FGH_PFNGLENABLEVERTEXATTRIBARRAYPROC fghEnableVertexAttribArray;
++FGH_PFNGLDISABLEVERTEXATTRIBARRAYPROC fghDisableVertexAttribArray;
++FGH_PFNGLVERTEXATTRIBPOINTERPROC fghVertexAttribPointer;
++#endif
+ 
+ void FGAPIENTRY glutSetVertexAttribCoord3(GLint attrib) {
+   if (fgStructure.CurrentWindow != NULL)
+--- a/src/fg_gl2.h
++++ b/src/fg_gl2.h
+@@ -67,13 +67,13 @@
+ typedef void (APIENTRY *FGH_PFNGLDISABLEVERTEXATTRIBARRAYPROC) (GLuint);
+ typedef void (APIENTRY *FGH_PFNGLVERTEXATTRIBPOINTERPROC) (GLuint index, GLint size, GLenum type, GLboolean normalized, GLsizei stride, const GLvoid *pointer);
+ 
+-FGH_PFNGLGENBUFFERSPROC fghGenBuffers;
+-FGH_PFNGLDELETEBUFFERSPROC fghDeleteBuffers;
+-FGH_PFNGLBINDBUFFERPROC fghBindBuffer;
+-FGH_PFNGLBUFFERDATAPROC fghBufferData;
+-FGH_PFNGLENABLEVERTEXATTRIBARRAYPROC fghEnableVertexAttribArray;
+-FGH_PFNGLDISABLEVERTEXATTRIBARRAYPROC fghDisableVertexAttribArray;
+-FGH_PFNGLVERTEXATTRIBPOINTERPROC fghVertexAttribPointer;
++extern FGH_PFNGLGENBUFFERSPROC fghGenBuffers;
++extern FGH_PFNGLDELETEBUFFERSPROC fghDeleteBuffers;
++extern FGH_PFNGLBINDBUFFERPROC fghBindBuffer;
++extern FGH_PFNGLBUFFERDATAPROC fghBufferData;
++extern FGH_PFNGLENABLEVERTEXATTRIBARRAYPROC fghEnableVertexAttribArray;
++extern FGH_PFNGLDISABLEVERTEXATTRIBARRAYPROC fghDisableVertexAttribArray;
++extern FGH_PFNGLVERTEXATTRIBPOINTERPROC fghVertexAttribPointer;
+ 
+ #    endif