Thank you for your replay. That's OK if C99 support both kinds of comment style.
———————————————————————————————————————————————— > chaihaoyu <chaihao...@huawei.com> writes: > >> Hi, recently I found some code style problems while using checkpatch.pl >> tool,please review. >> >> Date: Tue, 3 Nov 2020 11:01:40 +0800 >> signed-off-by: Haoyu Chai<chaihao...@huawei.com> >> --- >> softmmu/memory.c | 2 +- >> softmmu/memory_mapping.c | 2 +- >> softmmu/physmem.c | 2 +- >> 3 files changed, 3 insertions(+), 3 deletions(-) >> >> diff --git a/softmmu/memory.c b/softmmu/memory.c >> index 107ce0a4f8..5fb591b001 100644 >> --- a/softmmu/memory.c >> +++ b/softmmu/memory.c >> @@ -36,7 +36,7 @@ >> #include "hw/boards.h" >> #include "migration/vmstate.h" >> >> -//#define DEBUG_UNASSIGNED >> +/* #define DEBUG_UNASSIGNED */ >> >> static unsigned memory_region_transaction_depth; >> static bool memory_region_update_pending; >> diff --git a/softmmu/memory_mapping.c b/softmmu/memory_mapping.c >> index 18d0b8067c..f64053499e 100644 >> --- a/softmmu/memory_mapping.c >> +++ b/softmmu/memory_mapping.c >> @@ -19,7 +19,7 @@ >> #include "exec/memory.h" >> #include "exec/address-spaces.h" >> >> -//#define DEBUG_GUEST_PHYS_REGION_ADD >> +/* #define DEBUG_GUEST_PHYS_REGION_ADD */ >> >> static void memory_mapping_list_add_mapping_sorted(MemoryMappingList *list, >> MemoryMapping *mapping) >> diff --git a/softmmu/physmem.c b/softmmu/physmem.c >> index 44ffb60b5d..78c1b6580a 100644 >> --- a/softmmu/physmem.c >> +++ b/softmmu/physmem.c >> @@ -75,7 +75,7 @@ >> #include <daxctl/libdaxctl.h> >> #endif >> >> -//#define DEBUG_SUBPAGE >> +/* #define DEBUG_SUBPAGE */ >> >> /* ram_list is read under rcu_read_lock()/rcu_read_unlock(). Writes >> * are protected by the ramlist lock. > > I recommend to leave these alone. > > CODING_STYLE.rst: > > Rationale: The // form is valid in C99, so this is purely a matter of > consistency of style. The checkpatch script will warn you about this. > > For "real" comments, we overwhelmingly use /* */, and avoiding // makes > sense. Most exceptions are in code we copy from elsewhere, such as > disas/libvixl/. > > For commenting out *code*, we use both forms. Here are the counts for > commenting out macro definitions: > > $ git-grep '^/\* *# *define' | wc -l > 125 > $ git-grep '^// *# *define' | wc -l > 192 > > . >