#pragma Directives Overview Index

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C++Builder supports the following #pragma directives:

Directive	Description	Classic Compiler	Clang Compiler
#pragma comment	Writes a comment record in the object file. This can include linking to a library module. See Auto Linking for more information.
#pragma link	Instructs the linker to link the file into an executable file. See Auto Linking for more information.
#pragma exit	Indicates a function to be run on program exit (before _exit).
#pragma message	Prints the specified message at compile time.
#pragma package	Controls the initialization order of packages and other aspects related to packages.
#pragma resource	Emits a comment record that instructs the linker to mark the file as a form unit.
#pragma startup	Indicates a function to be run on program startup (before main).
#pragma alias	Indicates that two identifier names are equivalent.
#pragma alignment	Prints the alignment setting and enum size.
#pragma anon_struct	Allows compiling anonymous structures.
#pragma argsused	Inhibits warning about unused arguments.
#pragma checkoption	Verifies that the specified options are set.
#pragma codeseg	Indicates the code segment for function allocation.
#pragma codestring	Emits bytes into the code segment.
#pragma defineonoption	Defines the specified symbol if the specified options are set.
#pragma delphiheader	Indicates the bounds of a Delphi header.
#pragma explicit_rtti	Specifies for what class or record members (public, protected, and so on) RTTI should be generated.
#pragma extref	Forces an external reference for the specified symbol.
#pragma hdrfile	Specifies the name of the precompiled header.
#pragma hdrignore	Obsolete.
#pragma hdrstop	Stops the precompiling after the current header.
#pragma implements	Emits a comment record containing the name of the current unit to the object file.
#pragma init_seg	Affects the order in which startup code is executed.
#pragma inline	Causes the compiler to restart itself with the option -B.
#pragma intrinsic	Overrides the options that control the inlining of functions.
#pragma nopushoptwarn	Suppresses the warnings about mismatched #pragma option push/pop.
#pragma nopackwarning	Suppresses the warnings about mismatched #pragma pack push/pop.
#pragma noretval	Indicates that a function doesn't return.
#pragma obsolete	Indicates that the specified symbol is obsolete.
#pragma once	Indicates that the current header file must be included once.
#pragma option	Saves the current options and sets the specified options.
#pragma pack	Sets the structure packing alignment.
#pragma region/end_region	Indicates code regions. Used by the IDE editor for code folding.
#pragma samecodeseg	Places the specified functions in the same code segment.
#pragma sizeof	Prints the size of the specified aggregate.
#pragma sysheader	Indicates the bounds of a system header.
#pragma undefineonoption	Undefines the specified symbol if the specified options are set.
#pragma warn	Enables/disables warnings.

Note: For many of the #pragma directives supported only by the Classic compiler, the Clang compiler silently accepts them but does not actually do anything.

Note: To view all Clang pragmas see Clang's Compiler User Manual.