diff --git a/src/glsl/standalone_scaffolding.cpp b/src/glsl/standalone_scaffolding.cpp
index 33d3804c670..ccf5b4f8d60 100644
--- a/src/glsl/standalone_scaffolding.cpp
+++ b/src/glsl/standalone_scaffolding.cpp
@@ -33,6 +33,24 @@
 #include <string.h>
 #include "ralloc.h"
 
+void
+_mesa_warning(struct gl_context *ctx, const char *fmt, ...)
+{
+    va_list vargs;
+    (void) ctx;
+
+    va_start(vargs, fmt);
+
+    /* This output is not thread-safe, but that's good enough for the
+     * standalone compiler.
+     */
+    fprintf(stderr, "Mesa warning: ");
+    vfprintf(stderr, fmt, vargs);
+    fprintf(stderr, "\n");
+
+    va_end(vargs);
+}
+
 void
 _mesa_reference_shader(struct gl_context *ctx, struct gl_shader **ptr,
                        struct gl_shader *sh)
diff --git a/src/glsl/standalone_scaffolding.h b/src/glsl/standalone_scaffolding.h
index 41ce35befc6..096b2f114c7 100644
--- a/src/glsl/standalone_scaffolding.h
+++ b/src/glsl/standalone_scaffolding.h
@@ -33,6 +33,9 @@
 
 #include "main/mtypes.h"
 
+extern "C" void
+_mesa_warning(struct gl_context *ctx, const char *fmtString, ... );
+
 extern "C" void
 _mesa_reference_shader(struct gl_context *ctx, struct gl_shader **ptr,
                        struct gl_shader *sh);