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Is there a way to override functions with static scope within an object module? If I start with something like this, a module with global symbol "foo" is a function that calls local symbol "bar," that calls local symbol "baz" [scameron@localhost ~]$ cat foo.c #include <stdio.h> static void baz(void) { printf("baz\n"); } static void bar(void) { printf("bar\n"); baz(); } void foo(void) { printf("foo\n"); bar(); } [scameron@localhost ~]$ gcc -g -c foo.c [scameron@localhost ~]$ objdump -x foo.o | egrep 'foo|bar|baz' foo.o: file format elf32-i386 foo.o 00000000 l df *ABS* 00000000 foo.c 00000000 l F .text 00000014 baz 00000014 l F .text 00000019 bar 0000002d g F .text 00000019 foo It has one global, "foo" and two locals "bar" and "baz." Suppose I want to write some unit tests that exercise bar and baz, I can do: [scameron@localhost ~]$ cat barbaz bar baz [scameron@localhost ~]$ objcopy --globalize-symbols=barbaz foo.o foo2.o [scameron@localhost ~]$ objdump -x foo2.o | egrep 'foo|bar|baz' foo2.o: file format elf32-i386 foo2.o 00000000 l df *ABS* 00000000 foo.c 00000000 g F .text 00000014 baz 00000014 g F .text 00000019 bar 0000002d g F .text 00000019 foo [scameron@localhost ~]$ And now bar and baz are global symbols and accessible from outside the module. So far so good. But what if I want to interpose my own function on top of "baz", and have "bar" call my interposed "baz"? Is there a way to do that? --wrap option doesn't seem to do it... [scameron@localhost ~]$ cat ibaz.c #include <stdio.h> extern void foo(); extern void bar(); void __wrap_baz() { printf("wrapped baz\n"); } int main(int argc, char *argv[]) { foo(); baz(); } [scameron@localhost ~]$ gcc -o ibaz ibaz.c foo2.o -Xlinker --wrap -Xlinker baz [scameron@localhost ~]$ ./ibaz foo bar baz wrapp

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