re PR middle-end/24295 (Xorg broken, #pragma weak foo = bar no longer causes bar to be referenced)

gcc/ChangeLog:
PR middle-end/24295
* cgraphunit.c (cgraph_varpool_remove_unreferenced_decls): Mark
alias targets.
* varasm.c (find_decl_and_mark_needed): After cgraph global info
is ready, stop marking functions, but still mark variables.
gcc/testsuite/ChangeLog:
PR middle-end/24295
* g++.old-deja/g++.abi/vtable2.C: Do not introduce external
declarations with the same names as thunks' alias targets, use
aliases instead.
* gcc.dg/attr-alias-3.c: New test.
* gcc.dg/weak/weak-14.c, gcc.dg/weak/weak-14a.c: New test.

From-SVN: r105688

1 files changed, 33 insertions, 0 deletions

diff --git a/gcc/testsuite/gcc.dg/weak/weak-14.c b/gcc/testsuite/gcc.dg/weak/weak-14.c
new file mode 100644
index 0000000..fa15624
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/weak/weak-14.c
@@ -0,0 +1,33 @@
+// { dg-do run }
+// { dg-require-weak "" }
+// { dg-options "-O2 -fno-common" }
+
+// Copyright 2005 Free Software Foundation, Inc.
+// Contributed by Alexandre Oliva <aoliva@redhat.com>
+
+// PR middle-end/24295
+
+// The unit-at-a-time call graph code used to fail to emit variables
+// without external linkage that were only used indirectly, through
+// aliases.  We might then get linker failures because the static
+// variable was not defined, or run-time errors because the weak alias
+// ended up pointing somewhere random.
+
+#include <stdlib.h>
+
+static unsigned long lv1 = 0xdeadbeefUL;
+#pragma weak Av1a = lv1
+extern unsigned long Av1a;
+
+static unsigned long lf1(void) { return 0x510bea7UL; }
+#pragma weak Af1a = lf1
+extern unsigned long Af1a(void);
+
+int main (void) {
+  if (! &Av1a
+      || ! &Af1a
+      || Av1a != 0xdeadbeefUL
+      || Af1a() != 0x510bea7UL)
+    abort ();
+  exit (0);
+}