math/stp: remove nonsensical sbrk use

This code called sbrk(4000000) and beyond error checking ignored
the result meaning the 4MB of address space allocated could
never be used without another call to sbrk and reference to
INITIAL_MEMORY_PREALLOCATION_SIZE, but nothing in the repo does
either.

Submitted upstream as stp/stp#474

Approved by:	arrowd (maintainer)
Sponsored by:	DARPA
Differential Revision:	https://reviews.freebsd.org/D42978

math/stp/Makefile

@@ -1,6 +1,6 @@
 PORTNAME=	stp
 DISTVERSION=	2.3.3
-PORTREVISION=	11
+PORTREVISION=	12
 PORTEPOCH=	1
 CATEGORIES=	math
 
@@ -11,9 +11,6 @@ WWW=		https://stp.github.io/
 LICENSE=	MIT
 LICENSE_FILE=	${WRKSRC}/LICENSE
 
-BROKEN_aarch64=		fails to link: missing sbrk
-BROKEN_riscv64=		fails to link: missing sbrk
-
 LIB_DEPENDS=	libboost_program_options.so:devel/boost-libs \
 		libminisat.so:math/minisat \
 		libcryptominisat5.so:math/cryptominisat

math/stp/files/patch-tools_stp_main__common.cpp

@@ -0,0 +1,45 @@
+--- tools/stp/main_common.cpp.orig
++++ tools/stp/main_common.cpp
+@@ -27,16 +27,8 @@
+ #include "stp/Parser/parser.h"
+ #include "stp/cpp_interface.h"
+
+-//for srbk() function
+-#if !defined(__MINGW32__) && !defined(__MINGW64__) && !defined(_MSC_VER)
+-#include <unistd.h>
+-#endif
+-
+ extern void errorHandler(const char* error_msg);
+
+-// Amount of memory to ask for at beginning of main.
+-extern const intptr_t INITIAL_MEMORY_PREALLOCATION_SIZE;
+-
+ using namespace stp;
+ using std::unique_ptr;
+ using std::cout;
+@@ -49,9 +41,6 @@
+   exit(-1);
+ }
+
+-// Amount of memory to ask for at beginning of main.
+-const intptr_t INITIAL_MEMORY_PREALLOCATION_SIZE = 4000000;
+-
+ Main::Main() : onePrintBack(false)
+ {
+   bm = NULL;
+@@ -62,15 +51,6 @@
+
+   // Register the error handler
+   vc_error_hdlr = errorHandler;
+-
+-#if !defined(__MINGW32__) && !defined(__MINGW64__) && !defined(_MSC_VER)
+-  // Grab some memory from the OS upfront to reduce system time when
+-  // individual hash tables are being allocated
+-  if (sbrk(INITIAL_MEMORY_PREALLOCATION_SIZE) == ((void*)-1))
+-  {
+-    FatalError("Initial allocation of memory failed.");
+-  }
+-#endif
+
+   bm = new STPMgr();
+   GlobalParserBM = bm;