From 870abf1514830e06cfb90d8d751bf914b925e053 Mon Sep 17 00:00:00 2001
From: Armin Luntzer <armin.luntzer@univie.ac.at>
Date: Wed, 4 Sep 2019 16:18:15 +0200
Subject: [PATCH] basic fixup to compile with bcc2 gcc/clang
---
Makefile | 3 ++-
arch/sparc/Makefile | 7 ++++++-
arch/sparc/include/asm/thread.h | 5 +++--
arch/sparc/kernel/bootmem.c | 20 ++++++++++++++++++++
arch/sparc/kernel/ttable.S | 8 ++++----
include/kernel/kthread.h | 6 ++++++
include/kernel/types.h | 4 +++-
lib/vsnprintf.c | 2 +-
8 files changed, 45 insertions(+), 10 deletions(-)
diff --git a/Makefile b/Makefile
index a01f208..70a15ef 100644
--- a/Makefile
+++ b/Makefile
@@ -464,7 +464,8 @@ ARCH_AFLAGS :=
ARCH_CFLAGS :=
-include arch/$(ARCH)/Makefile
-KBUILD_CFLAGS += $(call cc-option,-fno-delete-null-pointer-checks,)
+# XXX unsuppported by clang
+#KBUILD_CFLAGS += $(call cc-option,-fno-delete-null-pointer-checks,)
ifdef CONFIG_CC_OPTIMIZE_NONE
KBUILD_CFLAGS += -O0 $(call cc-disable-warning,maybe-uninitialized,)
diff --git a/arch/sparc/Makefile b/arch/sparc/Makefile
index 5ec8266..7073823 100644
--- a/arch/sparc/Makefile
+++ b/arch/sparc/Makefile
@@ -1 +1,6 @@
-ARCH_CFLAGS = -mcpu=v8
+# gcc (7.2.0)
+ARCH_CFLAGS = -mcpu=leon3 -mfix-gr712rc
+# gcc (4.x)
+#ARCH_CFLAGS = -mcpu=v8 -mfix-gr712rc
+# clang
+#ARCH_CFLAGS = -mcpu=gr712rc
diff --git a/arch/sparc/include/asm/thread.h b/arch/sparc/include/asm/thread.h
index 0e8b431..c34aa50 100644
--- a/arch/sparc/include/asm/thread.h
+++ b/arch/sparc/include/asm/thread.h
@@ -36,10 +36,11 @@ struct thread_info {
int softirq_count;
int hardirq_count;
- uint32_t __unused;
+ /* bcc is stupid and does not respect the aligned attribute */
+ int unused;
/* Context switch saved kernel state. */
- unsigned long ksp; /* ... ksp __attribute__ ((aligned (8))); */
+ unsigned long ksp __attribute__ ((aligned (8)));
unsigned long kpc;
unsigned long kpsr;
unsigned long kwim;
diff --git a/arch/sparc/kernel/bootmem.c b/arch/sparc/kernel/bootmem.c
index 26241a7..c5f20ac 100644
--- a/arch/sparc/kernel/bootmem.c
+++ b/arch/sparc/kernel/bootmem.c
@@ -251,7 +251,27 @@ void bootmem_init(void)
/* now add the remaining memory banks */
+
+ /**
+ * XXX bcc2 (sparc-gaisler-elf-gcc) 7.2.0 screws this up by swallowing
+ * a cmp; bne sequence after the call to page_map_add and placing
+ * the required ret; restore sequence along with some instructions
+ * for one of the BUG() related printks lower down in the remaining
+ * instruction. The function consequently never returns, and partially
+ * removing sections of this loop results in apparent random BUG()s,
+ * because all of the generated instructions are ordered to the end of
+ * the function. The reason appears to be some flawed optimisation
+ * heuristic, because the problem goes away, when SPARC_PHYS_BANKS
+ * is set to a value > 0, which means that sp_banks will have
+ * more than a single entry and the check of base_pfn vs the
+ * bank's base address results in the rest of the loop being taken.
+ */
+#define BCC2_IS_RETARDED
+#ifdef BCC2_IS_RETARDED
+ for (i = 0; i <= SPARC_PHYS_BANKS; i++) {
+#else
for (i = 0; sp_banks[i].num_bytes != 0; i++) {
+#endif
BUG_ON(i > SPARC_PHYS_BANKS);
diff --git a/arch/sparc/kernel/ttable.S b/arch/sparc/kernel/ttable.S
index 6d86481..9ee8915 100644
--- a/arch/sparc/kernel/ttable.S
+++ b/arch/sparc/kernel/ttable.S
@@ -131,14 +131,14 @@ mna_trap_handler:
fpe_trap_handler:
.global tag_overflow_trap_handler
tag_overflow_trap_handler:
- .global mna_trap_handler
-mna_trap_handler:
+# .global mna_trap_handler /* CLANG! */
+#mna_trap_handler:
.global cpdis_trap_handler
cpdis_trap_handler:
.global cpex_trap_handler
cpex_trap_handler:
- .global fpe_trap_handler
-fpe_trap_handler:
+# .global fpe_trap_handler
+#fpe_trap_handler:
.global hw_div0_trap_handler
hw_div0_trap_handler:
.global nmi_entry
diff --git a/include/kernel/kthread.h b/include/kernel/kthread.h
index 2f860ec..9a2d141 100644
--- a/include/kernel/kthread.h
+++ b/include/kernel/kthread.h
@@ -69,6 +69,12 @@ struct task_struct {
struct sched_attr attr;
+
+ /* bcc is SO extremely stupid, it misaligns 64-bit types and generates
+ * ldd's to laod them; also, it does not respect the aligned attribute
+ */
+ int unused;
+
ktime runtime; /* remaining runtime in this period */
ktime wakeup; /* start of next period */
ktime deadline; /* deadline of current period */
diff --git a/include/kernel/types.h b/include/kernel/types.h
index 25948df..09df928 100644
--- a/include/kernel/types.h
+++ b/include/kernel/types.h
@@ -28,6 +28,8 @@
#if defined(GCC_VERSION) && (GCC_VERSION >= 40402)
#include <stdint.h>
#else
+#include <stdint.h>
+#if 0 /* XXX need CLANG FIX */
/* this must do... */
typedef unsigned long uintptr_t;
typedef signed long intptr_t;
@@ -52,7 +54,7 @@ compile_time_assert(sizeof(uint16_t) == 2, TYPES_UINT16_SIZE_INVALID);
compile_time_assert(sizeof( int16_t) == 2, TYPES__INT16_SIZE_INVALID);
compile_time_assert(sizeof(uint8_t) == 1, TYPES_UINT_8_SIZE_INVALID);
compile_time_assert(sizeof( int8_t) == 1, TYPES__INT_8_SIZE_INVALID);
-
+#endif
#endif
#ifndef __SIZEOF_LONG__
diff --git a/lib/vsnprintf.c b/lib/vsnprintf.c
index 746328f..695a81c 100644
--- a/lib/vsnprintf.c
+++ b/lib/vsnprintf.c
@@ -265,7 +265,7 @@ static size_t eval_flags(const char *fmt, struct fmt_spec *spec)
static size_t eval_width(const char *fmt, struct fmt_spec *spec, va_list *args)
{
- int w;
+ int w = 0;
char *end;
--
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