mdio, phy: fix -Wshadow warnings triggered by nested container_of()
container_of() macro hides a local variable '__mptr' inside. This becomes a problem when several container_of() are nested in each other within single line or plain macros. As C preprocessor doesn't support generating random variable names, the sole solution is to avoid defining macros that consist only of container_of() calls, or they will self-shadow '__mptr' each time: In file included from ./include/linux/bitmap.h:10, from drivers/net/phy/phy_device.c:12: drivers/net/phy/phy_device.c: In function ‘phy_device_release’: ./include/linux/kernel.h:693:8: warning: declaration of ‘__mptr’ shadows a previous local [-Wshadow] 693 | void *__mptr = (void *)(ptr); \ | ^~~~~~ ./include/linux/phy.h:647:26: note: in expansion of macro ‘container_of’ 647 | #define to_phy_device(d) container_of(to_mdio_device(d), \ | ^~~~~~~~~~~~ ./include/linux/mdio.h:52:27: note: in expansion of macro ‘container_of’ 52 | #define to_mdio_device(d) container_of(d, struct mdio_device, dev) | ^~~~~~~~~~~~ ./include/linux/phy.h:647:39: note: in expansion of macro ‘to_mdio_device’ 647 | #define to_phy_device(d) container_of(to_mdio_device(d), \ | ^~~~~~~~~~~~~~ drivers/net/phy/phy_device.c:217:8: note: in expansion of macro ‘to_phy_device’ 217 | kfree(to_phy_device(dev)); | ^~~~~~~~~~~~~ ./include/linux/kernel.h:693:8: note: shadowed declaration is here 693 | void *__mptr = (void *)(ptr); \ | ^~~~~~ ./include/linux/phy.h:647:26: note: in expansion of macro ‘container_of’ 647 | #define to_phy_device(d) container_of(to_mdio_device(d), \ | ^~~~~~~~~~~~ drivers/net/phy/phy_device.c:217:8: note: in expansion of macro ‘to_phy_device’ 217 | kfree(to_phy_device(dev)); | ^~~~~~~~~~~~~ As they are declared in header files, these warnings are highly repetitive and very annoying (along with the one from linux/pci.h). Convert the related macros from linux/{mdio,phy}.h to static inlines to avoid self-shadowing and potentially improve bug-catching. No functional changes implied. Signed-off-by:Alexander Lobakin <alobakin@pm.me> Reviewed-by:
Andrew Lunn <andrew@lunn.ch> Link: https://lore.kernel.org/r/20210116161246.67075-1-alobakin@pm.me Signed-off-by:
Jakub Kicinski <kuba@kernel.org>
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dc9c9e72
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