Re: [PATCH v2 5/6] PCI: iproc: fix -Wvoid-pointer-to-enum-cast warning

[Manivannan Sadhasivam <mani@kernel.org>]

On Tue, Nov 14, 2023 at 02:54:55PM +0900, Yoshihiro Shimoda wrote:
> From: Justin Stitt <justinstitt@google.com>
> 
> When building with clang 18 I see the following warning:
> |       drivers/pci/controller/pcie-iproc-platform.c:55:15: warning: cast to smaller
> |                integer type 'enum iproc_pcie_type' from 'const void *' [-Wvoid-pointer-to-enum-cast]
> |          55 |         pcie->type = (enum iproc_pcie_type) of_device_get_match_data(dev);
> 
> This is due to the fact that `of_device_get_match_data` returns a void*
> while `enum iproc_pcie_type` has the size of an int. This leads to
> truncation and possible data loss.
> 

As Geert noted, this statement is wrong as there is no possible data loss in
this driver. Please fix it in next version.

> Link: https://github.com/ClangBuiltLinux/linux/issues/1910
> Reported-by: Nathan Chancellor <nathan@kernel.org>
> Signed-off-by: Justin Stitt <justinstitt@google.com>
> Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>

Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

- Mani

> ---
>  drivers/pci/controller/pcie-iproc-platform.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/pci/controller/pcie-iproc-platform.c b/drivers/pci/controller/pcie-iproc-platform.c
> index acdc583d2980..83cbc95f4384 100644
> --- a/drivers/pci/controller/pcie-iproc-platform.c
> +++ b/drivers/pci/controller/pcie-iproc-platform.c
> @@ -52,7 +52,7 @@ static int iproc_pltfm_pcie_probe(struct platform_device *pdev)
>  	pcie = pci_host_bridge_priv(bridge);
>  
>  	pcie->dev = dev;
> -	pcie->type = (enum iproc_pcie_type) of_device_get_match_data(dev);
> +	pcie->type = (uintptr_t) of_device_get_match_data(dev);
>  
>  	ret = of_address_to_resource(np, 0, &reg);
>  	if (ret < 0) {
> -- 
> 2.34.1
> 

-- 
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