--- mpich-3.4.1/src/mpl/configure.ac~	2021-01-20 19:04:56.000000000 +0100
+++ mpich-3.4.1/src/mpl/configure.ac	2021-05-17 09:45:20.178904241 +0200
@@ -426,99 +426,7 @@
 
     linux86_cycle|linux86_cycle_2)
     
-# The following AC_TRY_RUN statements are needed because x86_64 compilers
-# usually know about rdtscp but the cpu may or may not actually implement the
-# feature.  This is not cross-compile safe, unfortunately.  In the long run we
-# should allow the user to override this with a configure flag.
-    AC_CACHE_CHECK([that linux86 cycle counter is available],
-        pac_cv_linux86_cycle,
-            AC_TRY_RUN([
-int main()
-{
-    /* rdtscp */
-    long long var, *var_ptr=&var;
-    __asm__ __volatile__("rdtscp; shl \$32, %%rdx; or %%rdx, %%rax" : "=a" (*var_ptr) : : "ecx", "rdx");
-    return 0;
-}
-            ],pac_cv_linux86_cycle=rdtscp,
-                AC_TRY_RUN([[
-int main()
-{
-    /* cpuid 64 */
-    long long var, *var_ptr=&var;
-    __asm__ __volatile__("push %%rbx ; cpuid ; rdtsc ; pop %%rbx ; shl $32, %%rdx; or %%rdx, %%rax" : "=a" (*var_ptr) : : "ecx", "rdx");
-    return 0;
-}
-                ]],pac_cv_linux86_cycle=cpuid_rdtsc64,
-                    AC_TRY_RUN([[[
-int main()
-{
-    /* cpuid 32 */
-    long long var, *var_ptr=&var;
-    __asm__ __volatile__("push %%ebx ; cpuid ; rdtsc ; pop %%ebx" : "=A" (*var_ptr) : : "ecx");
-    return 0;
-}
-                    ]]],pac_cv_linux86_cycle=cpuid_rdtsc32,
-                        AC_TRY_RUN([[[[
-int main()
-{
-    /* simple */
-    long long var, *var_ptr=&var;
-    __asm__ __volatile__("rdtsc" : "=A" (*var_ptr));
-    return 0;
-}
-                        ]]]],pac_cv_linux86_cycle=rdtsc,
-                        pac_cv_linux86_cycle=no)
-                    )
-                ),
-dnl The if-cross-compiling clause from the first AC_TRY_RUN.  Hope that if the
-dnl compiler knows about the instruction then it's supported by the target
-dnl platform.
-                AC_TRY_COMPILE(,[[
-                    long long var, *var_ptr=&var;
-                    __asm__ __volatile__("rdtscp; shl \$32, %%rdx; or %%rdx, %%rax" : "=a" (*var_ptr) : : "ecx", "rdx");
-                ]],pac_cv_linux86_cycle=rdtscp,
-                    AC_TRY_COMPILE(,[[[
-                        long long var, *var_ptr=&var;
-                        __asm__ __volatile__("push %%rbx ; cpuid ; rdtsc ; pop %%rbx ; shl $32, %%rdx; or %%rdx, %%rax" : "=a" (*var_ptr) : : "ecx", "rdx");
-                    ]]],pac_cv_linux86_cycle=cpuid_rdtsc64,
-                        AC_TRY_COMPILE(,[[[[
-                            long long var, *var_ptr=&var;
-                            __asm__ __volatile__("push %%ebx ; cpuid ; rdtsc ; pop %%ebx" : "=A" (*var_ptr) : : "ecx");
-                        ]]]],pac_cv_linux86_cycle=cpuid_rdtsc32,
-                            AC_TRY_COMPILE(,[[[[[
-                                long long var, *var_ptr=&var;
-                                __asm__ __volatile__("rdtsc" : "=A" (*var_ptr));
-                            ]]]]],pac_cv_linux86_cycle=rdtsc,
-                            pac_cv_linux86_cycle=no)
-                        )
-                    )
-                )
-            )
-    )
-
-    case "$pac_cv_linux86_cycle" in
-        "rdtscp")
-            AC_DEFINE(LINUX86_CYCLE_RDTSCP,1,[Define which x86 cycle counter to use])
-	    ;;
-        "cpuid_rdtsc64")
-            AC_DEFINE(LINUX86_CYCLE_CPUID_RDTSC64,1,[Define which x86 cycle counter to use])
-            ;;
-        "cpuid_rdtsc32")
-            AC_DEFINE(LINUX86_CYCLE_CPUID_RDTSC32,1,[Define which x86 cycle counter to use])
-	    ;;
-        "rdtsc")
-            AC_DEFINE(LINUX86_CYCLE_RDTSC,1,[Define which x86 cycle counter to use])
-	    ;;
-        *)
-            cpu_gcc_x86_cycle=no
-	    ;;
-    esac
-
-    if test "$cpu_gcc_x86_cycle" = "no" ; then
-        AC_MSG_ERROR([Linux86 cycle counter is not available on this system and or with the $CC compiler])
-    fi
-    MPL_TIMER_TYPE="long long"
+    AC_MSG_ERROR([Linux86 cycle counter is not available])
     ;;
 
     gcc_ia64_cycle)