tracetool: carefully define SDT_USE_VARIADIC

The dtrace backend defines SDT_USE_VARIADIC as a workaround for a conflict with a LTTng UST header file, which requires SDT_USE_VARIADIC to be defined. LTTng UST <lttng/tracepoint.h> breaks if included after generated dtrace headers because SDT_USE_VARIADIC will already be defined: #ifdef LTTNG_UST_HAVE_SDT_INTEGRATION #define SDT_USE_VARIADIC <-- error, it's already defined #include <sys/sdt.h> Be more careful when defining SDT_USE_VARIADIC. This fixes the build when both the dtrace and ust tracers are enabled at the same time. Fixes: 27e08ba ("tracetool: work around ust <sys/sdt.h> include conflict") Signed-off-by: Stefan Hajnoczi <[email protected]> Message-id: [email protected] Signed-off-by: Stefan Hajnoczi <[email protected]>
tx2rx · Jul 30, 2020 · 0008224 · 0008224
1 parent 1b7157b
commit 0008224
Showing 1 changed file with 4 additions and 0 deletions.
diff --git a/scripts/tracetool/backend/dtrace.py b/scripts/tracetool/backend/dtrace.py
@@ -44,11 +44,15 @@ def generate_h_begin(events, group):
     # require SDT_USE_VARIADIC to be defined. If dtrace includes <sys/sdt.h>
     # first without defining SDT_USE_VARIADIC then ust breaks because the
     # STAP_PROBEV() macro is not defined.
+    out('#ifndef SDT_USE_VARIADIC')
     out('#define SDT_USE_VARIADIC 1')
+    out('#endif')
 
     out('#include "%s"' % header,
         '')
 
+    out('#undef SDT_USE_VARIADIC')
+
     # SystemTap defines <provider>_<name>_ENABLED() but other DTrace
     # implementations might not.
     for e in events: