Red Hat ENTERPRISE LINUX 4 Manual page 39

Chapter 4. GCC Command Options
The
-fobjc-exceptions
execution:
@synchronized (ObjCClass *guard) {
...
}
Upon entering the
has been placed on the corresponding
shall wait until the other thread relinquishes its lock. Once
thread will place its own lock on it, execute the code contained in the
and finally relinquish the lock (thereby making
Unlike Java, Objective-C does not allow for entire methods to be marked
that throwing exceptions out of
object to be unlocked properly.
-freplace-objc-classes
Emit a special marker instructing
to load it in at run time instead. This is used in conjunction with the Fix-and-Continue
dyld(1)
debugging mode, where the object file in question may be recompiled and dynamically reloaded
in the course of program execution, without the need to restart the program itself. Currently, Fix-
and-Continue functionality is only available in conjunction with the NeXT runtime on Mac OS
X 10.3 and later.
-fzero-link
When compiling for the NeXT runtime, the compiler ordinarily replaces calls to
objc_getClass("...")
with static class references that get initialized at load time, which improves run-time
performance. Specifying the
objc_getClass("...")
allows for individual class implementations to be modified during program execution.
-gen-decls
Dump interface declarations for all classes seen in the source file to a file named
.decl
sourcename
-Wno-protocol
If a class is declared to implement a protocol, a warning is issued for every method in the protocol
that is not implemented by the class. The default behavior is to issue a warning for every method
not explicitly implemented in the class, even if a method implementation is inherited from the
superclass. If you use the
are considered to be implemented, and no warning is issued for them.
-Wselector
Warn if multiple methods of different types for the same selector are found during compilation.
The check is performed on the list of methods in the final stage of compilation. Additionally,
a check is performed for each selector appearing in a
responding method for that selector has been found during compilation. Because these checks
scan the method table only at the end of compilation, these warnings are not produced if the final
stage of compilation is not reached, for example because an error is found during compilation,
or because the
-fsyntax-only
-Wundeclared-selector
Warn if a
@selector(...)
selector is considered undeclared if no method with that name has been declared before the
switch also enables the use of synchronization blocks for thread-safe
block, a thread of execution shall first check whether a lock
@synchronized
guard
@synchronized
ld(1)
(when the name of the class is known at compile time)
-fzero-link
to be retained. This is useful in Zero-Link debugging mode, since it
.
-Wno-protocol
option is being used.
expression referring to an undeclared selector is found. A
object by another thread. If it has, the current thread
guard
available to other threads).
guard
blocks is allowed, and will cause the guarding
not to statically link in the resulting object file, and allow
flag suppresses this behavior and causes calls to
option, then methods inherited from the superclass
@selector(...)
becomes available, the current
@synchronized
@synchronized
expression, and a cor-
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block,
. Note