code: drawterm

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allocate 2 ulongs for secalloc() to keep it 8 byte aligned (use first ulong for magic constant)

on sparc64, secalloc needs to return 8 byte aligned pointer,
so we allocate two ulongs instead of one and use the first
one for the magic constant 0x5ECA110C.

--- a/kern/alloc.c

+++ b/kern/alloc.c

@@ -16,12 +16,17 @@

 	return mallocz(n, 1);

 }

+enum {

+	SECMAGIC = 0x5ECA110C,

+};

+

 void*

 secalloc(ulong n)

 {

-	void *p = mallocz(n+sizeof(ulong), 1);

-	*(ulong*)p = n;

-	return (ulong*)p+1;

+	void *p = mallocz(n+sizeof(ulong)*2, 1);

+	((ulong*)p)[0] = SECMAGIC;

+	((ulong*)p)[1] = n;

+	return (ulong*)p+2;

 }

 void

@@ -28,7 +33,8 @@

 secfree(void *p)

 {

 	if(p != nil){

+		assert(((ulong*)p)[-2] == SECMAGIC);

 		memset(p, 0, ((ulong*)p)[-1]);

-		free((ulong*)p-1);

+		free((ulong*)p-2);

 	}

 }