dbug: correct trace for DBUG_RETURN(func()); -- gcc only

when func1 calls func2 from DBUG_RETURN, dbug shows the trace as
| > func1
| < func1
| > func2
| < func2
because DBUG_LEAVE happens before func2(). Change that to invoke
DBUG_LEAVE when the local variable goes out of scope. This uses
gcc specific __attribute__((cleanup)).

1 files changed, 8 insertions, 0 deletions

diff --git a/configure.cmake b/configure.cmake
index 1dade02aa32..e8d29c5bf5f 100644
--- a/configure.cmake
+++ b/configure.cmake
@@ -910,6 +910,14 @@ CHECK_C_SOURCE_COMPILES("
     HAVE_WEAK_SYMBOL
 )
 
+CHECK_C_SOURCE_COMPILES("
+    void foo(int *x) { }
+    int main() {
+      int a __attribute__((cleanup(foo)));
+      return 0;
+    }"
+    HAVE_ATTRIBUTE_CLEANUP
+)
 
 CHECK_CXX_SOURCE_COMPILES("
     #include <new>