diff --git a/src/mesa/main/arbprogram.c b/src/mesa/main/arbprogram.c
index fbfd4a0385f..3911e55217c 100644
--- a/src/mesa/main/arbprogram.c
+++ b/src/mesa/main/arbprogram.c
@@ -382,7 +382,7 @@ set_program_string(struct gl_program *prog, GLenum target, GLenum format, GLsize
    gl_shader_stage stage = _mesa_program_enum_to_shader_stage(target);
 
    uint8_t sha1[SHA1_DIGEST_LENGTH];
-   _mesa_sha1_compute(string, strlen(string), sha1);
+   _mesa_sha1_compute(string, len, sha1);
 
    /* Dump original shader source to MESA_SHADER_DUMP_PATH and replace
     * if corresponding entry found from MESA_SHADER_READ_PATH.