diff options
| -rw-r--r-- | src/mesa/main/buffers.c | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/src/mesa/main/buffers.c b/src/mesa/main/buffers.c index 818d068a12b..85db3868c49 100644 --- a/src/mesa/main/buffers.c +++ b/src/mesa/main/buffers.c @@ -290,7 +290,10 @@ _mesa_DrawBuffersARB(GLsizei n, const GLenum *buffers) GET_CURRENT_CONTEXT(ctx); ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx); - if (n < 1 || n > (GLsizei) ctx->Const.MaxDrawBuffers) { + /* Turns out n==0 is a valid input that should not produce an error. + * The remaining code below correctly handles the n==0 case. + */ + if (n < 0 || n > (GLsizei) ctx->Const.MaxDrawBuffers) { _mesa_error(ctx, GL_INVALID_VALUE, "glDrawBuffersARB(n)"); return; } @@ -332,12 +335,14 @@ _mesa_DrawBuffersARB(GLsizei n, const GLenum *buffers) _mesa_drawbuffers(ctx, n, buffers, destMask); /* - * Call device driver function. + * Call device driver function. Note that n can be equal to 0, + * in which case we don't want to reference buffers[0], which + * may not be valid. */ if (ctx->Driver.DrawBuffers) ctx->Driver.DrawBuffers(ctx, n, buffers); else if (ctx->Driver.DrawBuffer) - ctx->Driver.DrawBuffer(ctx, buffers[0]); + ctx->Driver.DrawBuffer(ctx, n>0? buffers[0]:GL_NONE); } |