Re: Weak globals

On Apr 2, 2019, at 8:43 AM, Joe Pluta <joepluta@xxxxxxxxxxxxxxxxx> wrote:

Has anybody successfully used the weak #pragma for a function? I'm trying to create a service program with three modules: one that references a function, one with that function defined weakly, and one with the function defined strongly. In that scenario, I should be able to combine the following:

Reference, weak: calls weak
Reference, strong: calls strong
Reference, weak, strong: calls strong
Reference only: won't compile

The best example code I found was in the AIX reference:

https://www.ibm.com/support/knowledgecenter/SSGH3R_13.1.0/com.ibm.xlcpp131.aix.doc/compiler_ref/prag_weak.html

From what I can tell, that same syntax should work in the ILE compiler, so I created the following:

|// TFOO1.CPP #include <stdio.h> void foo(); int main() { foo(); } // TFOO2.CPP #include <stdio.h> #pragma weak foo__Fv void foo() { printf("Foo called from compilation unit 2\n"); } // TFOO3.CPP #include <stdio.h> void foo() { printf("Foo called from compilation unit 3\n"); } |


CRTSRVPGM TFOO MODULES(TFOO1 TFOO2 TFOO3) EXPORT(*ALL) fails with CPD5D03, Definition supplied multiple times for symbol 'foo__Fv'.

I can get around it with OPTION(*DUPPROC) but then I have to be very careful of the order of my modules in the MODULES keyword of CRTSRVPGM (and even then the order isn't _guaranteed_). That also would hide any cases of unintentional procedure duplication, so I'd really like to get #pragma weak working.


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