Expand the header comment to clarify the purpose for the

sqlite3MemoryBarrier() function.

FossilOrigin-Name: b89495ae09aa0e9652475b2ba1943dfd87c73e07

diff --git a/manifest b/manifest
index 60536e3e34ed4633ae31692c5c0ec5589d07d787..e46cf93be819e443b15bb21d3aef0e5fe0aed273 100644 (file)
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Remove\san\sassert\sin\sthe\swindows\sworker-thread\slogic\sthat\scan\sfail\sin\sa\srace\ncondition.
-D 2015-09-26T01:28:46.988
+C Expand\sthe\sheader\scomment\sto\sclarify\sthe\spurpose\sfor\sthe\nsqlite3MemoryBarrier()\sfunction.
+D 2015-09-26T03:23:29.340
 F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f
 F Makefile.in e1afa6fb2de2bddd50e0ddae8166c2ee9d69b301
 F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23
@@ -317,8 +317,8 @@ F src/msvc.h d9ba56c6851227ab44b3f228a35f3f5772296495
 F src/mutex.c 8e45800ee78e0cd1f1f3fe8e398853307f4a085c
 F src/mutex.h 779d588e3b7756ec3ecf7d78cde1d84aba414f85
 F src/mutex_noop.c 9d4309c075ba9cc7249e19412d3d62f7f94839c4
-F src/mutex_unix.c 8cfa6e83c618d2fcae0fe63f4d2b5bb16b11a97a
-F src/mutex_w32.c 2e025e6642eaf27597403690980f560d1a91f62c
+F src/mutex_unix.c a94b46f3f7beba307dde1b298b0f99f9c3677a93
+F src/mutex_w32.c b483d3e5914b84c82516a6a9919582f12ef3b838
 F src/notify.c 9711a7575036f0d3040ba61bc6e217f13a9888e7
 F src/os.c 8fd25588eeba74068d41102d26810e216999b6c8
 F src/os.h 3e57a24e2794a94d3cf2342c6d9a884888cd96bf
@@ -1388,7 +1388,7 @@ F tool/vdbe_profile.tcl 67746953071a9f8f2f668b73fe899074e2c6d8c1
 F tool/warnings-clang.sh f6aa929dc20ef1f856af04a730772f59283631d4
 F tool/warnings.sh 48bd54594752d5be3337f12c72f28d2080cb630b
 F tool/win/sqlite.vsix deb315d026cc8400325c5863eef847784a219a2f
-P 2d867c054d6d3e1e841ba9ca524e986bc6993ac3
-R 1758ec9357330b0579141ecae96a2702
+P d7bfb96092a6b812af194f32b22283a0f6a7da96
+R 53a860536ab1d397fede465244d51351
 U drh
-Z da76e4bf593addae8cb1880d2dd70b45
+Z f65cf73c8cac5f871fc434c67cdccd1a

diff --git a/manifest.uuid b/manifest.uuid
index ba759293c93d1be8c1c2ec5c43045f993ea5c2b4..eab8e97c0aa917a8d7ab0e18aca454114b368244 100644 (file)
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-d7bfb96092a6b812af194f32b22283a0f6a7da96
\ No newline at end of file
+b89495ae09aa0e9652475b2ba1943dfd87c73e07
\ No newline at end of file

diff --git a/src/mutex_unix.c b/src/mutex_unix.c
index cebb96c90e806faacf4b90fe170a6996c6bddf42..dbdaa225b3e2def6c1d9702c89f62f832f159392 100644 (file)
--- a/src/mutex_unix.c
+++ b/src/mutex_unix.c
@@ -81,7 +81,9 @@ static int pthreadMutexNotheld(sqlite3_mutex *p){
 #endif
 
 /*
-** Try to provide a memory barrier operation, needed for initialization only.
+** Try to provide a memory barrier operation, needed for initialization
+** and also for the implementation of xShmBarrier in the VFS in cases
+** where SQLite is compiled without mutexes.
 */
 void sqlite3MemoryBarrier(void){
 #if defined(SQLITE_MEMORY_BARRIER)

diff --git a/src/mutex_w32.c b/src/mutex_w32.c
index 90be07db2ddcd7ee9e8ef162769e865e1568b56a..7d28e4defc9ea0345a87be26d41a3f6157b6297f 100644 (file)
--- a/src/mutex_w32.c
+++ b/src/mutex_w32.c
@@ -78,7 +78,9 @@ static int winMutexNotheld(sqlite3_mutex *p){
 #endif
 
 /*
-** Try to provide a memory barrier operation, needed for initialization only.
+** Try to provide a memory barrier operation, needed for initialization
+** and also for the xShmBarrier method of the VFS in cases when SQLite is
+** compiled without mutexes (SQLITE_THREADSAFE=0).
 */
 void sqlite3MemoryBarrier(void){
 #if defined(SQLITE_MEMORY_BARRIER)