https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97537
Bug ID: 97537
Summary: gcc -H Option Issue, incomplete dependency tree
listing
Product: gcc
Version: unknown
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: adrien.guichard at citel dot fr
Target Milestone: ---
Created attachment 49426
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=49426&action=edit
source code sample showing the issue.
Copied from Stack Overflow: "GCC -H option issue (header dependency tree
listing)"
https://stackoverflow.com/questions/58864013/gcc-h-option-issue-header-dependency-tree-listing
If the content of an included header file evaluates to empty string during
repeated inclusion (because of the content being enclosed in an #ifndef
statement), then the included header file name is not listed as a dependency of
any subsequent header files.
Example:
$ cat main.cpp
#include "header1.h"
int main(void) {
return 0;
}
$ cat header1.h
#ifndef header1_h
#define header1_h
#include "header2.h"
#include "header3.h"
#endif
$ cat header2.h
#ifndef header2_h
#define header2_h
#include "header3.h"
#endif
$ cat header3.h
#ifndef header3_h
#define header3_h
void header3_function1(void);
#endif
$ gcc -H main.cpp
. header1.h
.. header2.h
... header3.h
Problem:
We would expect header3.h to be a dependency of header1.h.
Expected output:
. header1.h
.. header2.h
... header3.h
.. header3.h
Using the attached file:
$ tar xvfz h-option-test-case.tar.gz
$ cd h-option-test-case/
$ gcc -H main.cpp
Thanks for your support,
Adrien
