From: Marc Fournier <marc.fournier@camptocamp.com>
Date: Fri, 1 May 2015 18:40:59 +0000 (+0200)
Subject: Turbostat: confine AC_COMPILE_IFELSE() inside a AC_CACHE_CHECK block
X-Git-Tag: collectd-5.5.0~24^2~4
X-Git-Url: https://git.octo.it/?p=collectd.git;a=commitdiff_plain;h=dfe9bb8c5c2f2baaa9c2be9ceddf61248b5effb7

Turbostat: confine AC_COMPILE_IFELSE() inside a AC_CACHE_CHECK block

The previous way of doing worked as expected, but didn't print out
anything in the summary, making it difficult to know why the plugin
wasn't built on older systems.
---

diff --git a/configure.ac b/configure.ac
index 2ef82ee1..90420f8d 100644
--- a/configure.ac
+++ b/configure.ac
@@ -593,10 +593,23 @@ AC_CHECK_HEADERS(termios.h, [have_termios_h="yes"])
 have_asm_msrindex_h="no"
 AC_CHECK_HEADERS(asm/msr-index.h, [have_asm_msrindex_h="yes"])
 
-have_usable_asm_msrindex_h="no"
 if test "x$have_asm_msrindex_h" = "xyes"
 then
-	AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[#include<asm/msr-index.h>]],[[int y = MSR_CORE_C3_RESIDENCY;]])], [have_usable_asm_msrindex_h="yes"])
+  AC_CACHE_CHECK([whether asm/msr-index.h has MSR_CORE_C3_RESIDENCY],
+                 [c_cv_have_usable_asm_msrindex_h],
+                 AC_COMPILE_IFELSE([AC_LANG_PROGRAM(
+[[[
+#include<asm/msr-index.h>
+]]],
+[[[
+int y = MSR_CORE_C3_RESIDENCY;
+return(y);
+]]]
+  )],
+                 [c_cv_have_usable_asm_msrindex_h="yes"],
+                 [c_cv_have_usable_asm_msrindex_h="no"],
+                                  )
+                 )
 fi
 
 have_cpuid_h="no"
@@ -5199,7 +5212,7 @@ then
 	then
 		plugin_ipvs="yes"
 	fi
-	if test "x$have_usable_asm_msrindex_h" = "xyes" && test "x$have_cpuid_h" = "xyes"
+	if test "x$c_cv_have_usable_asm_msrindex_h" = "xyes" && test "x$have_cpuid_h" = "xyes"
 	then
 		plugin_turbostat="yes"
 	fi