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| author |   Arnd Bergmann <arnd@arndb.de> | 2017-07-19 14:53:00 +0200 |
|---|---|---|
| committer |   Ingo Molnar <mingo@kernel.org> | 2017-07-20 10:46:24 +0200 |
| commit | 75e2f0a6b16141cb347f442033ec907380d4d66e (patch) | |
| tree | 95da28d4ab0ea6a7d902f4c63c61f9f5cca8cc82 /arch/x86 | |
| parent | perf/x86: Shut up false-positive -Wmaybe-uninitialized warning (diff) | |
| download | linux-dev-75e2f0a6b16141cb347f442033ec907380d4d66e.tar.xz linux-dev-75e2f0a6b16141cb347f442033ec907380d4d66e.zip | |
x86/fpu/math-emu: Fix possible uninitialized variable use
When building the kernel with "make EXTRA_CFLAGS=...", this overrides
the "PARANOID" preprocessor macro defined in arch/x86/math-emu/Makefile,
and we run into a build warning:
arch/x86/math-emu/reg_compare.c: In function ‘compare_i_st_st’:
arch/x86/math-emu/reg_compare.c:254:6: error: ‘f’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
This fixes the implementation to work correctly even without the PARANOID
flag, and also fixes the Makefile to not use the EXTRA_CFLAGS variable
but instead use the ccflags-y variable in the Makefile that is meant
for this purpose.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Bill Metzenthen <billm@melbpc.org.au>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20170719125310.2487451-3-arnd@arndb.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86')
| -rw-r--r-- | arch/x86/math-emu/Makefile | 4 | ||||
| -rw-r--r-- | arch/x86/math-emu/reg_compare.c | 16 |
2 files changed, 10 insertions, 10 deletions
diff --git a/arch/x86/math-emu/Makefile b/arch/x86/math-emu/Makefile index 9b0c63b60302..1b2dac174321 100644 --- a/arch/x86/math-emu/Makefile +++ b/arch/x86/math-emu/Makefile @@ -5,8 +5,8 @@ #DEBUG = -DDEBUGGING DEBUG = PARANOID = -DPARANOID -EXTRA_CFLAGS := $(PARANOID) $(DEBUG) -fno-builtin $(MATH_EMULATION) -EXTRA_AFLAGS := $(PARANOID) +ccflags-y += $(PARANOID) $(DEBUG) -fno-builtin $(MATH_EMULATION) +asflags-y += $(PARANOID) # From 'C' language sources: C_OBJS =fpu_entry.o errors.o \ diff --git a/arch/x86/math-emu/reg_compare.c b/arch/x86/math-emu/reg_compare.c index b77360fdbf4a..19b33b50adfa 100644 --- a/arch/x86/math-emu/reg_compare.c +++ b/arch/x86/math-emu/reg_compare.c @@ -168,7 +168,7 @@ static int compare(FPU_REG const *b, int tagb) /* This function requires that st(0) is not empty */ int FPU_compare_st_data(FPU_REG const *loaded_data, u_char loaded_tag) { - int f = 0, c; + int f, c; c = compare(loaded_data, loaded_tag); @@ -189,12 +189,12 @@ int FPU_compare_st_data(FPU_REG const *loaded_data, u_char loaded_tag) case COMP_No_Comp: f = SW_C3 | SW_C2 | SW_C0; break; -#ifdef PARANOID default: +#ifdef PARANOID EXCEPTION(EX_INTERNAL | 0x121); +#endif /* PARANOID */ f = SW_C3 | SW_C2 | SW_C0; break; -#endif /* PARANOID */ } setcc(f); if (c & COMP_Denormal) { @@ -205,7 +205,7 @@ int FPU_compare_st_data(FPU_REG const *loaded_data, u_char loaded_tag) static int compare_st_st(int nr) { - int f = 0, c; + int f, c; FPU_REG *st_ptr; if (!NOT_EMPTY(0) || !NOT_EMPTY(nr)) { @@ -235,12 +235,12 @@ static int compare_st_st(int nr) case COMP_No_Comp: f = SW_C3 | SW_C2 | SW_C0; break; -#ifdef PARANOID default: +#ifdef PARANOID EXCEPTION(EX_INTERNAL | 0x122); +#endif /* PARANOID */ f = SW_C3 | SW_C2 | SW_C0; break; -#endif /* PARANOID */ } setcc(f); if (c & COMP_Denormal) { @@ -283,12 +283,12 @@ static int compare_i_st_st(int nr) case COMP_No_Comp: f = X86_EFLAGS_ZF | X86_EFLAGS_PF | X86_EFLAGS_CF; break; -#ifdef PARANOID default: +#ifdef PARANOID EXCEPTION(EX_INTERNAL | 0x122); +#endif /* PARANOID */ f = 0; break; -#endif /* PARANOID */ } FPU_EFLAGS = (FPU_EFLAGS & ~(X86_EFLAGS_ZF | X86_EFLAGS_PF | X86_EFLAGS_CF)) | f; if (c & COMP_Denormal) { |