The bus parameter in the macro PCI_BUILD_BDF is not surrounded by
parenthesis. This can create a compile error when warnings are
treated as errors or can potentially create runtime errors due to the
operator precedence.
For instance:
file.c:x:32: error: suggest parentheses around '-' inside '<<'
[-Werror=parentheses]
171 | uint16_t bdf = PCI_BUILD_BDF(a - b, sdev->devfn);
| ~~^~~
include/hw/pci/pci.h:19:41: note: in definition of macro
'PCI_BUILD_BDF'
19 | #define PCI_BUILD_BDF(bus, devfn) ((bus << 8) | (devfn))
| ^~~
cc1: all warnings being treated as errors
Signed-off-by: Roque Arcudia Hernandez <roqueh@google.com>
Reviewed-by: Nabih Estefan <nabihestefan@google.com>
---
include/hw/pci/pci.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/include/hw/pci/pci.h b/include/hw/pci/pci.h
index 35d4fe0bbf..1daec974da 100644
--- a/include/hw/pci/pci.h
+++ b/include/hw/pci/pci.h
@@ -16,7 +16,7 @@ extern bool pci_available;
#define PCI_BUS_NUM(x) (((x) >> 8) & 0xff)
#define PCI_SLOT(devfn) (((devfn) >> 3) & 0x1f)
#define PCI_FUNC(devfn) ((devfn) & 0x07)
-#define PCI_BUILD_BDF(bus, devfn) ((bus << 8) | (devfn))
+#define PCI_BUILD_BDF(bus, devfn) (((bus) << 8) | (devfn))
#define PCI_BDF_TO_DEVFN(x) ((x) & 0xff)
#define PCI_BUS_MAX 256
#define PCI_DEVFN_MAX 256