#pragma comment

Applicable invocations

Table 1. Invocations that accept the given pragma
Pragma	xlc (Compiling C)	xlC (Compiling C++)	xlclang (Compiling C)	xlclang++ (Compiling C++)
`#pragma comment`	✓	✓

Note: Only typical invocations are listed in this table. You can refer to the full list of compiler invocations for all basic invocations and their equivalent special invocations.

Purpose

Places a comment into the object module.

Syntax

Parameters

compiler: Appends the name and version of the compiler at the end of the generated object module.
date: The date and time of the compilation are appended at the end of the generated object module.
timestamp: Appends the date and time of the last modification of the source at the end of the generated object module.
copyright: Places the text specified by the token_sequence, if any, into the generated object module. The token_sequence is included in the generated executable and loaded into memory when the program is run.
user: Places the text specified by the token_sequence, if any, into the generated object module. The token_sequence is included in the generated executable but is not loaded into memory when the program is run.
token_sequence: The characters in this field, if specified, must be enclosed in double quotation marks ("). If the string literal specified in the token_sequence exceeds 32 767 bytes, an information message is emitted and the pragma is ignored.

Usage

More than one comment directive can appear in a translation unit, and each type of comment directive can appear more than once, with the exception of copyright, which can appear only once.

You can display the object-file comments by using the operating system strings command.

Examples

Assume that the code of tt.c is as follows:

#pragma comment(date)
#pragma comment(compiler)
#pragma comment(timestamp)
#pragma comment(copyright,"My copyright")
int main() { return 0; }

To display the comment information embedded in tt.o, along with any other strings that can be found in the code, issue the command:

xlc -c tt.c
strings -a tt.o

The preceding code might produce the following results:

@.text
.data
@.bss
.comment
Thu Dec 24 16:44:25 EDT 2018IBM XL C for AIX ---- Version 16.1.0.0
Thu Dec 24 16:44:09 EDT 2018
main
My copyright
.file
tt.c
.text
.data
.bss
.main
_$STATIC
_$STATIC
main
main
Thu Dec 24 16:44:25 2018
IBM XL C for AIX, Version 16.1.0.0 ---