diff -up chromium-88.0.4324.182/third_party/swiftshader/src/OpenGL/libEGL/BUILD.gn.gcc-swiftshader-visibility chromium-88.0.4324.182/third_party/swiftshader/src/OpenGL/libEGL/BUILD.gn
--- chromium-88.0.4324.182/third_party/swiftshader/src/OpenGL/libEGL/BUILD.gn.gcc-swiftshader-visibility	2021-02-25 16:31:51.929335783 +0000
+++ chromium-88.0.4324.182/third_party/swiftshader/src/OpenGL/libEGL/BUILD.gn	2021-02-25 16:31:51.929335783 +0000
@@ -42,7 +42,8 @@ config("swiftshader_libEGL_private_confi
     } else if (is_clang) {
       defines += [ "EGLAPI=__attribute__((visibility(\"protected\"))) __attribute__((no_sanitize(\"function\")))" ]
     } else {
-      defines += [ "EGLAPI= " ]
+      cflags += [ "-fvisibility=protected" ]
+      defines += [ "EGLAPI=__attribute__((visibility(\"protected\")))" ]
     }
   }
 }
diff -up chromium-88.0.4324.182/third_party/swiftshader/src/OpenGL/libGLESv2/BUILD.gn.gcc-swiftshader-visibility chromium-88.0.4324.182/third_party/swiftshader/src/OpenGL/libGLESv2/BUILD.gn
--- chromium-88.0.4324.182/third_party/swiftshader/src/OpenGL/libGLESv2/BUILD.gn.gcc-swiftshader-visibility	2021-02-25 18:16:28.576901417 +0000
+++ chromium-88.0.4324.182/third_party/swiftshader/src/OpenGL/libGLESv2/BUILD.gn	2021-02-25 18:17:50.356567690 +0000
@@ -57,7 +57,8 @@ config("swiftshader_libGLESv2_private_co
     } else if (is_clang) {
       defines += [ "GL_APICALL=__attribute__((visibility(\"protected\"))) __attribute__((no_sanitize(\"function\")))" ]
     } else {
-      defines += [ "GL_APICALL= " ]
+      cflags += [ "-fvisibility=protected" ]
+      defines += [ "GL_APICALL=__attribute__((visibility(\"protected\")))" ]
     }
   }
 }