Do not directly call imported functions

This is needed by Gentoo's sci-libs/lapack-3.9.0-r1 package.

mold.h

@@ -1770,8 +1770,12 @@ public:
         : ctx.dynbss->shdr.sh_addr + value;
     }
 
-    if (has_plt(ctx) && esym().st_type == STT_GNU_IFUNC)
-      return get_plt_addr(ctx);
+    if (has_plt(ctx)) {
+      if (esym().st_type == STT_GNU_IFUNC)
+        return get_plt_addr(ctx);
+      if (is_imported)
+        return get_plt_addr(ctx);
+    }
 
     if (input_section) {
       if (input_section->is_ehframe) {
@@ -1793,12 +1797,8 @@ public:
         // relocations.
         return 0;
       }
-
       return input_section->get_addr() + value;
     }
-
-    if (has_plt(ctx))
-      return get_plt_addr(ctx);
     return value;
   }
 

test/plt-dso.sh

@@ -0,0 +1,40 @@
+#!/bin/bash
+set -e
+cd $(dirname $0)
+echo -n "Testing $(basename -s .sh $0) ... "
+t=$(pwd)/tmp/$(basename -s .sh $0)
+mkdir -p $t
+
+cat <<EOF | cc -fPIC -c -o $t/a.o -xc -
+#include <stdio.h>
+
+void world() {
+  printf("world\n");
+}
+
+void hello() {
+  printf("Hello ");
+  world();
+}
+EOF
+
+clang -fuse-ld=`pwd`/../mold -shared -o $t/b.so $t/a.o
+
+cat <<EOF | cc -c -o $t/c.o -xc -
+#include <stdio.h>
+
+void world() {
+  printf("WORLD\n");
+}
+
+void hello();
+
+int main() {
+  hello();
+}
+EOF
+
+clang -fuse-ld=`pwd`/../mold -o $t/exe -Wl,-rpath=$t $t/c.o $t/b.so
+$t/exe | grep -q 'Hello WORLD'
+
+echo OK