From d99aad8ee308600832da39105a6511275cfe32ad Mon Sep 17 00:00:00 2001
From: Chip-Kerchner <chip.kerchner@ibm.com>
Date: Tue, 14 Nov 2023 11:07:08 -0600
Subject: [PATCH] Fix older version of gcc - missing __has_builtin, cpuid and
 no support of P10.

---
 Makefile.power                | 12 ++++++++++++
 driver/others/dynamic_power.c | 17 ++++++++++++-----
 2 files changed, 24 insertions(+), 5 deletions(-)

diff --git a/Makefile.power b/Makefile.power
index 95bada34fc..aa1ca080a8 100644
--- a/Makefile.power
+++ b/Makefile.power
@@ -11,7 +11,19 @@ endif
 
 ifeq ($(CORE), POWER10)
 ifneq ($(C_COMPILER), PGI)
+ifeq ($(C_COMPILER), GCC))
+ifeq ($(GCCVERSIONGTEQ10), 1)
 CCOMMON_OPT += -Ofast -mcpu=power10 -mtune=power10 -mvsx -fno-fast-math
+else ifneq ($(GCCVERSIONGT4), 1)
+$(warning your compiler is too old to fully support POWER9, getting a newer version of gcc is recommended)
+CCOMMON_OPT += -Ofast -mcpu=power8 -mtune=power8 -mvsx -fno-fast-math
+else
+$(warning your compiler is too old to fully support POWER10, getting a newer version of gcc is recommended)
+CCOMMON_OPT += -Ofast -mcpu=power9 -mtune=power9 -mvsx -fno-fast-math
+endif
+else
+CCOMMON_OPT += -Ofast -mcpu=power10 -mtune=power10 -mvsx -fno-fast-math
+endif
 ifeq ($(F_COMPILER), IBM)
 FCOMMON_OPT += -O2 -qrecur -qnosave -qarch=pwr10 -qtune=pwr10 -qfloat=nomaf -qzerosize
 else
diff --git a/driver/others/dynamic_power.c b/driver/others/dynamic_power.c
index f0faf2bafc..0454f186cd 100644
--- a/driver/others/dynamic_power.c
+++ b/driver/others/dynamic_power.c
@@ -66,8 +66,7 @@ static int cpuid(void)
 #endif
     return CPU_UNKNOWN;
 }
-#else
-#if defined(C_PGI) || defined(__clang__)
+#elif defined(C_PGI) || defined(__clang__)
 /*
  * NV HPC compilers do not yet implement __builtin_cpu_is().
  * Fake a version here for use in the CPU detection code below.
@@ -196,13 +195,21 @@ static int cpuid(void)
 	cpu_type = pvrPOWER[i].cpu_type;
 	return (int)(cpu_type);
 }
-#endif  /* C_PGI */
+#elif !defined(__BUILTIN_CPU_SUPPORTS__)
+static int cpuid(void)
+{
+    return CPU_UNKNOWN;
+}
 #endif  /* _AIX */
 
 #ifndef __BUILTIN_CPU_SUPPORTS__
 #include <string.h>
 
-#if defined(_AIX) || (defined(__has_builtin) && !__has_builtin(__builtin_cpu_is))
+#ifndef __has_builtin
+#define __has_builtin(x)   0
+#endif
+
+#if defined(_AIX) || !__has_builtin(__builtin_cpu_is)
 static int __builtin_cpu_is(const char *arg)
 {
     static int ipinfo = -1;
@@ -227,7 +234,7 @@ static int __builtin_cpu_is(const char *arg)
 }
 #endif
 
-#if defined(_AIX) || (defined(__has_builtin) && !__has_builtin(__builtin_cpu_supports))
+#if defined(_AIX) || !__has_builtin(__builtin_cpu_supports)
 static int __builtin_cpu_supports(const char *arg)
 {
     return 0;