configure: Fix pkg-config test in absence of valgrind

The empty string used for the not case is replaced by the default
if-else clause and so causes the configure to fail in the absence of
valgrind. Which is not quite what was intended.

Instead use the common idiom of setting a variable depending on whether
the true or false branch is taken and emit the conditional code as a
second step.

Reported-by: Tobias Jakobi <liquid.acid@gmx.net>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

1 files changed, 4 insertions, 2 deletions

diff --git a/configure.ac b/configure.ac
index d72874bc..97bbcb72 100644
--- a/configure.ac
+++ b/configure.ac
@@ -261,8 +261,10 @@ if test "x$INTEL" != "xno" -o "x$RADEON" != "xno"; then
     fi
 fi
 
-PKG_CHECK_MODULES(VALGRIND, [valgrind],
-                  AC_DEFINE([HAVE_VALGRIND], 1, [Use valgrind intrinsics to suppress false warings]),)
+PKG_CHECK_MODULES(VALGRIND, [valgrind], [have_valgrind=yes], [have_valgrind=no])
+if test "x$have_valgrind" = "xyes"; then
+        AC_DEFINE([HAVE_VALGRIND], 1, [Use valgrind intrinsics to suppress false warnings])
+fi
 
 AM_CONDITIONAL(HAVE_INTEL, [test "x$INTEL" != "xno"])
 AM_CONDITIONAL(HAVE_RADEON, [test "x$RADEON" != "xno"])