search for: strongalias

...out ThinLTO, and am a little confused. Current (non-ThinLTO) behavior in some cases seems to depend on opt level. Example: $ cat weak12main.c extern void test2(); int main() { test2(); } $ cat weak1.c #include <stdio.h> void weakalias() __attribute__((weak, alias ("f"))); void strongalias() __attribute__((alias ("f"))); void f () __attribute__ ((weak)); void f() { printf("In weak1.c:f\n"); } void test1() { printf("Call f() from weak1.c:\n"); f(); printf("Call weakalias() from weak1.c:\n"); weakalias(); printf("Call strongalia...

...> > Hi Teresa, > > I think that to answer your question correctly it is helpful to consider what is going on at the object file level. For your test1.c we conceptually have a .text section containing the body of f, and then three symbols: > > .weak f > f = .text > .globl strongalias > strongalias = .text > .weak weakalias > weakalias = .text > > Note that f, strongalias and weakalias are not related at all, except that they happen to point to the same place. If f is overridden by a symbol in another object file, it does not affect the symbols strongalias and we...

...out when they are both in > > comdats. > > In the above example the "link/connection" is not broken. The original > @x and @y still refer to the same data, it is just that neither is used > in the final linked object. > Ok, thanks. But how does that property work the strongalias case from the original email. E.g.: @f = weak global ... @strongalias = alias @f What we had concluded was that it should be transformed into the following when this copy of @f is non-prevailing: @f = external global @f.llvm.1 = internal global ... // Internalized copy of original @f @strongal...

...gt; Hi Teresa, > > I think that to answer your question correctly it is helpful to consider > what is going on at the object file level. For your test1.c we conceptually > have a .text section containing the body of f, and then three symbols: > > .weak f > f = .text > .globl strongalias > strongalias = .text > .weak weakalias > weakalias = .text > > Note that f, strongalias and weakalias are not related at all, except that > they happen to point to the same place. If f is overridden by a symbol in > another object file, it does not affect the symbols strongali...

...gt;> >> I think that to answer your question correctly it is helpful to consider what is going on at the object file level. For your test1.c we conceptually have a .text section containing the body of f, and then three symbols: >> >> .weak f >> f = .text >> .globl strongalias >> strongalias = .text >> .weak weakalias >> weakalias = .text >> >> Note that f, strongalias and weakalias are not related at all, except that they happen to point to the same place. If f is overridden by a symbol in another object file, it does not affect the symbol...

...estion correctly it is helpful to consider what is going on at the object file level. For your test1.c we conceptually have a .text section containing the body of f, and then three symbols: >>>>> >>>>> .weak f >>>>> f = .text >>>>> .globl strongalias >>>>> strongalias = .text >>>>> .weak weakalias >>>>> weakalias = .text >>>>> >>>>> Note that f, strongalias and weakalias are not related at all, except that they happen to point to the same place. If f is overridden by a...

...ample: > > > > $ cat weak12main.c > > extern void test2(); > > int main() { > > test2(); > > } > > > > $ cat weak1.c > > #include <stdio.h> > > > > void weakalias() __attribute__((weak, alias ("f"))); > > void strongalias() __attribute__((alias ("f"))); > > > > void f () __attribute__ ((weak)); > > void f() > > { > > printf("In weak1.c:f\n"); > > } > > void test1() { > > printf("Call f() from weak1.c:\n"); > > f(); > >...