From 2562755ee78983930d0662fa4d3bc5e2ac166350 Mon Sep 17 00:00:00 2001 From: Eric Blake Date: Fri, 1 Dec 2017 17:24:32 -0600 Subject: maint: Fix macros with broken 'do/while(0); ' usage The point of writing a macro embedded in a 'do { ... } while (0)' loop (particularly if the macro has multiple statements or would otherwise end with an 'if' statement) is so that the macro can be used as a drop-in statement with the caller supplying the trailing ';'. Although our coding style frowns on brace-less 'if': if (cond) statement; else something else; that is the classic case where failure to use do/while(0) wrapping would cause the 'else' to pair with any embedded 'if' in the macro rather than the intended outer 'if'. But conversely, if the macro includes an embedded ';', then the same brace-less coding style would now have two statements, making the 'else' a syntax error rather than pairing with the outer 'if'. Thus, even though our coding style with required braces is not impacted, ending a macro with ';' makes our code harder to port to projects that use brace-less styles. The change should have no semantic impact. I was not able to fully compile-test all of the changes (as some of them are examples of the ugly bit-rotting debug print statements that are completely elided by default, and I didn't want to recompile with the necessary -D witnesses - cleaning those up is left as a bite-sized task for another day); I did, however, audit that for all files touched, all callers of the changed macros DID supply a trailing ';' at the callsite, and did not appear to be used as part of a brace-less conditional. Found mechanically via: $ git grep -B1 'while (0);' | grep -A1 \\\\ Signed-off-by: Eric Blake Acked-by: Cornelia Huck Reviewed-by: Michael S. Tsirkin Acked-by: Dr. David Alan Gilbert Message-Id: <20171201232433.25193-7-eblake@redhat.com> Reviewed-by: Juan Quintela Signed-off-by: Paolo Bonzini --- hw/misc/auxbus.c | 2 +- hw/misc/macio/mac_dbdma.c | 4 ++-- hw/misc/mmio_interface.c | 2 +- hw/misc/stm32f2xx_syscfg.c | 2 +- hw/misc/zynq_slcr.c | 2 +- 5 files changed, 6 insertions(+), 6 deletions(-) (limited to 'hw/misc') diff --git a/hw/misc/auxbus.c b/hw/misc/auxbus.c index 1182745044..b4cacd664b 100644 --- a/hw/misc/auxbus.c +++ b/hw/misc/auxbus.c @@ -40,7 +40,7 @@ if (DEBUG_AUX) { \ qemu_log("aux: " fmt , ## __VA_ARGS__); \ } \ -} while (0); +} while (0) #define TYPE_AUXTOI2C "aux-to-i2c-bridge" #define AUXTOI2C(obj) OBJECT_CHECK(AUXTOI2CState, (obj), TYPE_AUXTOI2C) diff --git a/hw/misc/macio/mac_dbdma.c b/hw/misc/macio/mac_dbdma.c index 0eddf2e700..1b2a69b3ef 100644 --- a/hw/misc/macio/mac_dbdma.c +++ b/hw/misc/macio/mac_dbdma.c @@ -52,7 +52,7 @@ if (DEBUG_DBDMA) { \ printf("DBDMA: " fmt , ## __VA_ARGS__); \ } \ -} while (0); +} while (0) #define DBDMA_DPRINTFCH(ch, fmt, ...) do { \ if (DEBUG_DBDMA) { \ @@ -60,7 +60,7 @@ printf("DBDMA[%02x]: " fmt , (ch)->channel, ## __VA_ARGS__); \ } \ } \ -} while (0); +} while (0) /* */ diff --git a/hw/misc/mmio_interface.c b/hw/misc/mmio_interface.c index 894e9801cb..3b0e2039a3 100644 --- a/hw/misc/mmio_interface.c +++ b/hw/misc/mmio_interface.c @@ -39,7 +39,7 @@ static uint64_t mmio_interface_counter; if (DEBUG_MMIO_INTERFACE) { \ qemu_log("mmio_interface: 0x%" PRIX64 ": " fmt, s->id, ## __VA_ARGS__);\ } \ -} while (0); +} while (0) static void mmio_interface_init(Object *obj) { diff --git a/hw/misc/stm32f2xx_syscfg.c b/hw/misc/stm32f2xx_syscfg.c index 7c45833d09..7f10195862 100644 --- a/hw/misc/stm32f2xx_syscfg.c +++ b/hw/misc/stm32f2xx_syscfg.c @@ -34,7 +34,7 @@ if (STM_SYSCFG_ERR_DEBUG >= lvl) { \ qemu_log("%s: " fmt, __func__, ## args); \ } \ -} while (0); +} while (0) #define DB_PRINT(fmt, args...) DB_PRINT_L(1, fmt, ## args) diff --git a/hw/misc/zynq_slcr.c b/hw/misc/zynq_slcr.c index 44304d48be..d6bdd027ef 100644 --- a/hw/misc/zynq_slcr.c +++ b/hw/misc/zynq_slcr.c @@ -30,7 +30,7 @@ fprintf(stderr, ": %s: ", __func__); \ fprintf(stderr, ## __VA_ARGS__); \ } \ - } while (0); + } while (0) #define XILINX_LOCK_KEY 0x767b #define XILINX_UNLOCK_KEY 0xdf0d -- cgit v1.2.1