13 files changed, 122 insertions, 569 deletions

diff --git a/Build/source/texk/web2c/Makefile.in b/Build/source/texk/web2c/Makefile.in
index 7f6da7d38e1..849f08cced8 100644
--- a/Build/source/texk/web2c/Makefile.in
+++ b/Build/source/texk/web2c/Makefile.in
@@ -896,7 +896,7 @@ am_libunilib_a_OBJECTS =  \
 libunilib_a_OBJECTS = $(am_libunilib_a_OBJECTS)
 libxetex_a_AR = $(AR) $(ARFLAGS)
 libxetex_a_LIBADD =
-am__libxetex_a_SOURCES_DIST = xetexdir/MathTable.h \
+am__libxetex_a_SOURCES_DIST = \
 	xetexdir/XeTeXFontInst.cpp xetexdir/XeTeXFontInst.h \
 	xetexdir/XeTeXFontMgr.cpp xetexdir/XeTeXFontMgr.h \
 	xetexdir/XeTeXLayoutInterface.cpp \
@@ -3631,7 +3631,7 @@ libxetex_a_CPPFLAGS = $(xetex_cppflags)
 libxetex_a_CFLAGS = $(WARNING_CFLAGS)
 libxetex_a_CXXFLAGS = # $(WARNING_CXXFLAGS)
 libxetex_a_OBJCXXFLAGS = # $(WARNING_OBJCXXFLAGS)
-libxetex_a_SOURCES = xetexdir/MathTable.h xetexdir/XeTeXFontInst.cpp \
+libxetex_a_SOURCES = xetexdir/XeTeXFontInst.cpp \
 	xetexdir/XeTeXFontInst.h xetexdir/XeTeXFontMgr.cpp \
 	xetexdir/XeTeXFontMgr.h xetexdir/XeTeXLayoutInterface.cpp \
 	xetexdir/XeTeXLayoutInterface.h xetexdir/XeTeXOTMath.cpp \
diff --git a/Build/source/texk/web2c/xetexdir/ChangeLog b/Build/source/texk/web2c/xetexdir/ChangeLog
index 598c92efd55..eef47f4e0ce 100644
--- a/Build/source/texk/web2c/xetexdir/ChangeLog
+++ b/Build/source/texk/web2c/xetexdir/ChangeLog
@@ -1,3 +1,7 @@
+2017-03-12  Akira Kakuto  <kakuto@fuk.kinidai.ac.jp>
+
+	* Sync with the upstream..
+
 2016-10-03  Akira Kakuto  <kakuto@fuk.kinidai.ac.jp>
 
 	* XeTeXOTMath.cpp: Sync with the upstream..
diff --git a/Build/source/texk/web2c/xetexdir/MathTable.h b/Build/source/texk/web2c/xetexdir/MathTable.h
deleted file mode 100644
index 589cc1a2658..00000000000
--- a/Build/source/texk/web2c/xetexdir/MathTable.h
+++ /dev/null
@@ -1,278 +0,0 @@
-/****************************************************************************\
- Part of the XeTeX typesetting system
- Copyright (c) 1994-2008 by SIL International
- Copyright (c) 2009 by Jonathan Kew
- Copyright (c) 2012 by Khaled Hosny
-
- SIL Author(s): Jonathan Kew
-
-Permission is hereby granted, free of charge, to any person obtaining
-a copy of this software and associated documentation files (the
-"Software"), to deal in the Software without restriction, including
-without limitation the rights to use, copy, modify, merge, publish,
-distribute, sublicense, and/or sell copies of the Software, and to
-permit persons to whom the Software is furnished to do so, subject to
-the following conditions:
-
-The above copyright notice and this permission notice shall be
-included in all copies or substantial portions of the Software.
-
-THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
-EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
-MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
-NONINFRINGEMENT. IN NO EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE
-FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
-CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
-WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
-
-Except as contained in this notice, the name of the copyright holders
-shall not be used in advertising or otherwise to promote the sale,
-use or other dealings in this Software without prior written
-authorization from the copyright holders.
-\****************************************************************************/
-
-#ifndef __MATHTABLE_H__
-#define __MATHTABLE_H__
-
-#ifndef ANY_NUMBER
-#define ANY_NUMBER 1
-#endif
-
-typedef uint16_t Offset;
-
-typedef struct {
-	int16_t		value;
-	Offset		deviceTable;
-} MathValueRecord;
-
-typedef struct {
-	GlyphID		start;
-	GlyphID		end;
-	int16_t		startCoverageIndex;
-} RangeRecord;
-
-typedef struct {
-	uint32_t	version;
-	Offset		mathConstants;
-	Offset		mathGlyphInfo;
-	Offset		mathVariants;
-} MathTableHeader;
-
-typedef struct {
-	uint16_t		scriptPercentScaleDown;
-	uint16_t		scriptScriptPercentScaleDown;
-	uint16_t		delimitedSubFormulaMinHeight;
-	uint16_t		displayOperatorMinHeight;
-	MathValueRecord mathLeading;
-	MathValueRecord axisHeight;
-	MathValueRecord accentBaseHeight;
-	MathValueRecord flattenedAccentBaseHeight;
-	MathValueRecord subscriptShiftDown;
-	MathValueRecord subscriptTopMax;
-	MathValueRecord subscriptBaselineDropMin;
-	MathValueRecord superscriptShiftUp;
-	MathValueRecord superscriptShiftUpCramped;
-	MathValueRecord superscriptBottomMin;
-	MathValueRecord superscriptBaselineDropMax;
-	MathValueRecord subSuperscriptGapMin;
-	MathValueRecord superscriptBottomMaxWithSubscript;
-	MathValueRecord spaceAfterScript;
-	MathValueRecord upperLimitGapMin;
-	MathValueRecord upperLimitBaselineRiseMin;
-	MathValueRecord lowerLimitGapMin;
-	MathValueRecord lowerLimitBaselineDropMin;
-	MathValueRecord stackTopShiftUp;
-	MathValueRecord stackTopDisplayStyleShiftUp;
-	MathValueRecord stackBottomShiftDown;
-	MathValueRecord stackBottomDisplayStyleShiftDown;
-	MathValueRecord stackGapMin;
-	MathValueRecord stackDisplayStyleGapMin;
-	MathValueRecord stretchStackTopShiftUp;
-	MathValueRecord stretchStackBottomShiftDown;
-	MathValueRecord stretchStackGapAboveMin;
-	MathValueRecord stretchStackGapBelowMin;
-	MathValueRecord fractionNumeratorShiftUp;
-	MathValueRecord fractionNumeratorDisplayStyleShiftUp;
-	MathValueRecord fractionDenominatorShiftDown;
-	MathValueRecord fractionDenominatorDisplayStyleShiftDown;
-	MathValueRecord fractionNumeratorGapMin;
-	MathValueRecord fractionNumDiisplayStyleGapMin;
-	MathValueRecord fractionRuleThickness;
-	MathValueRecord fractionDenominatorGapMin;
-	MathValueRecord fractionDenomDisplayStyleGapMin;
-	MathValueRecord skewedFractionHorizontalGap;
-	MathValueRecord skewedFractionVerticalGap;
-	MathValueRecord overbarVerticalGap;
-	MathValueRecord overbarRuleThickness;
-	MathValueRecord overbarExtraAscender;
-	MathValueRecord underbarVerticalGap;
-	MathValueRecord underbarRuleThickness;
-	MathValueRecord underbarExtraDescender;
-	MathValueRecord radicalVerticalGap;
-	MathValueRecord radicalDisplayStyleVerticalGap;
-	MathValueRecord radicalRuleThickness;
-	MathValueRecord radicalExtraAscender;
-	MathValueRecord radicalKernBeforeDegree;
-	MathValueRecord radicalKernAfterDegree;
-	uint16_t 		radicalDegreeBottomRaisePercent;
-} MathConstants;
-
-typedef enum {
-	unknown = -1,
-	scriptPercentScaleDown = 0,
-	scriptScriptPercentScaleDown,
-	delimitedSubFormulaMinHeight,
-	displayOperatorMinHeight,
-	mathLeading,
-	firstMathValueRecord = mathLeading,
-	axisHeight,
-	accentBaseHeight,
-	flattenedAccentBaseHeight,
-	subscriptShiftDown,
-	subscriptTopMax,
-	subscriptBaselineDropMin,
-	superscriptShiftUp,
-	superscriptShiftUpCramped,
-	superscriptBottomMin,
-	superscriptBaselineDropMax,
-	subSuperscriptGapMin,
-	superscriptBottomMaxWithSubscript,
-	spaceAfterScript,
-	upperLimitGapMin,
-	upperLimitBaselineRiseMin,
-	lowerLimitGapMin,
-	lowerLimitBaselineDropMin,
-	stackTopShiftUp,
-	stackTopDisplayStyleShiftUp,
-	stackBottomShiftDown,
-	stackBottomDisplayStyleShiftDown,
-	stackGapMin,
-	stackDisplayStyleGapMin,
-	stretchStackTopShiftUp,
-	stretchStackBottomShiftDown,
-	stretchStackGapAboveMin,
-	stretchStackGapBelowMin,
-	fractionNumeratorShiftUp,
-	fractionNumeratorDisplayStyleShiftUp,
-	fractionDenominatorShiftDown,
-	fractionDenominatorDisplayStyleShiftDown,
-	fractionNumeratorGapMin,
-	fractionNumDisplayStyleGapMin,
-	fractionRuleThickness,
-	fractionDenominatorGapMin,
-	fractionDenomDisplayStyleGapMin,
-	skewedFractionHorizontalGap,
-	skewedFractionVerticalGap,
-	overbarVerticalGap,
-	overbarRuleThickness,
-	overbarExtraAscender,
-	underbarVerticalGap,
-	underbarRuleThickness,
-	underbarExtraDescender,
-	radicalVerticalGap,
-	radicalDisplayStyleVerticalGap,
-	radicalRuleThickness,
-	radicalExtraAscender,
-	radicalKernBeforeDegree,
-	radicalKernAfterDegree,
-	lastMathValueRecord = radicalKernAfterDegree,
-	radicalDegreeBottomRaisePercent,
-	lastMathConstant = radicalDegreeBottomRaisePercent
-} mathConstantIndex;
-
-typedef struct {
-	uint16_t	minConnectorOverlap;
-	Offset		vertGlyphCoverage;
-	Offset		horizGlyphCoverage;
-	uint16_t	vertGlyphCount;
-	uint16_t	horizGlyphCount;
-	Offset		vertGlyphConstruction[ANY_NUMBER];
-	Offset		horizGlyphConstruction[ANY_NUMBER];
-} MathVariants;
-
-typedef struct {
-	GlyphID		variantGlyph;
-	uint16_t	advanceMeasurement;
-} MathGlyphVariantRecord;
-
-typedef struct {
-	Offset		glyphAssembly;
-	uint16_t	variantCount;
-	MathGlyphVariantRecord mathGlyphVariantRecord[ANY_NUMBER];
-} MathGlyphConstruction;
-
-typedef struct {
-	GlyphID		glyph;
-	uint16_t	startConnectorLength;
-	uint16_t	endConnectorLength;
-	uint16_t	fullAdvance;
-	uint16_t	partFlags;
-} GlyphPartRecord;
-#define fExtender	0x0001
-
-typedef struct {
-	MathValueRecord italicsCorrection;
-	uint16_t		partCount;
-	GlyphPartRecord partRecords[ANY_NUMBER];
-} GlyphAssembly;
-
-typedef struct {
-	Offset		mathItalicsCorrectionInfo;
-	Offset		mathTopAccentAttachment;
-	Offset		extendedShapeCoverage;
-	Offset		mathKernInfo;
-} MathGlyphInfo;
-
-typedef struct {
-	Offset		coverage;
-	uint16_t	italicsCorrectionCount;
-	MathValueRecord	italicsCorrection[ANY_NUMBER];
-} MathItalicsCorrectionInfo;
-
-typedef struct {
-	Offset		coverage;
-	uint16_t	topAccentAttachmentCount;
-	MathValueRecord	topAccentAttachment[ANY_NUMBER];
-} MathTopAccentAttachment;
-
-typedef struct {
-	Offset	topRight;
-	Offset	topLeft;
-	Offset	bottomRight;
-	Offset	bottomLeft;
-} MathKernInfoRecord;
-
-typedef struct {
-	Offset		coverage;
-	uint16_t	kernInfoCount;
-	MathKernInfoRecord kernInfo[ANY_NUMBER];
-} MathKernInfo;
-
-typedef struct {
-	uint16_t		heightCount;
-	MathValueRecord	height[ANY_NUMBER];
-/*
- * The offset of this will vary depending on the size of the height[] array,
- * so we have to compute it at runtime, not refer to a fixed field offset.
- *
-	MathValueRecord	kern[ANY_NUMBER];
- */
-} MathKernTable;
-
-typedef struct {
-    uint16_t	format;
-} Coverage;
-
-typedef struct {
-    uint16_t	format;
-    uint16_t	glyphCount;
-    GlyphID		glyphArray[ANY_NUMBER];
-} CoverageFormat1;
-
-typedef struct {
-    uint16_t	format;
-    uint16_t	rangeCount;
-    RangeRecord	rangeArray[ANY_NUMBER];
-} CoverageFormat2;
-
-#endif
diff --git a/Build/source/texk/web2c/xetexdir/XeTeXFontInst.cpp b/Build/source/texk/web2c/xetexdir/XeTeXFontInst.cpp
index afdb847862d..1778858e5b9 100644
--- a/Build/source/texk/web2c/xetexdir/XeTeXFontInst.cpp
+++ b/Build/source/texk/web2c/xetexdir/XeTeXFontInst.cpp
@@ -67,7 +67,6 @@ XeTeXFontInst::XeTeXFontInst(const char* pathname, int index, float pointSize, i
     , m_index(0)
     , m_ftFace(0)
     , m_hbFont(NULL)
-    , m_math(NULL)
 {
     if (pathname != NULL)
         initialize(pathname, index, status);
@@ -81,7 +80,6 @@ XeTeXFontInst::~XeTeXFontInst()
     }
     hb_font_destroy(m_hbFont);
     delete[] m_filename;
-    free(m_math);
 }
 
 /* HarfBuzz font functions */
@@ -388,14 +386,6 @@ XeTeXFontInst::getFontTable(OTTag tag) const
     return table;
 }
 
-char *
-XeTeXFontInst::getMathTable()
-{
-    if (m_math == NULL)
-        m_math = (char*) getFontTable(MATH_TAG);
-    return m_math;
-}
-
 void *
 XeTeXFontInst::getFontTable(FT_Sfnt_Tag tag) const
 {
diff --git a/Build/source/texk/web2c/xetexdir/XeTeXFontInst.h b/Build/source/texk/web2c/xetexdir/XeTeXFontInst.h
index 65e92933214..e666fa60bdc 100644
--- a/Build/source/texk/web2c/xetexdir/XeTeXFontInst.h
+++ b/Build/source/texk/web2c/xetexdir/XeTeXFontInst.h
@@ -50,8 +50,6 @@ authorization from the copyright holders.
 #include FT_FREETYPE_H
 #include FT_TRUETYPE_TABLES_H
 
-#define MATH_TAG HB_TAG('M','A','T','H')
-
 // create specific subclasses for each supported platform
 
 class XeTeXFontInst
@@ -72,7 +70,6 @@ protected:
 
     FT_Face m_ftFace;
     hb_font_t* m_hbFont;
-    char *m_math;
 
 public:
     XeTeXFontInst(float pointSize, int &status);
@@ -84,7 +81,6 @@ public:
 
     void *getFontTable(OTTag tableTag) const;
     void *getFontTable(FT_Sfnt_Tag tableTag) const;
-    char *getMathTable();
 
     const char *getFilename(uint32_t* index) const
     {
diff --git a/Build/source/texk/web2c/xetexdir/XeTeXLayoutInterface.cpp b/Build/source/texk/web2c/xetexdir/XeTeXLayoutInterface.cpp
index 4753a7064d1..5b2d2b53933 100644
--- a/Build/source/texk/web2c/xetexdir/XeTeXLayoutInterface.cpp
+++ b/Build/source/texk/web2c/xetexdir/XeTeXLayoutInterface.cpp
@@ -1018,8 +1018,5 @@ usingOpenType(XeTeXLayoutEngine engine)
 bool
 isOpenTypeMathFont(XeTeXLayoutEngine engine)
 {
-    if (engine->font->getMathTable() != NULL)
-        return true;
-    else
-        return false;
+    return hb_ot_math_has_data(hb_font_get_face(engine->font->getHbFont()));
 }
diff --git a/Build/source/texk/web2c/xetexdir/XeTeXLayoutInterface.h b/Build/source/texk/web2c/xetexdir/XeTeXLayoutInterface.h
index 5c510d11884..0e0193361bf 100644
--- a/Build/source/texk/web2c/xetexdir/XeTeXLayoutInterface.h
+++ b/Build/source/texk/web2c/xetexdir/XeTeXLayoutInterface.h
@@ -48,6 +48,7 @@ typedef struct XeTeXLayoutEngine_rec* XeTeXLayoutEngine;
 #include FT_TRUETYPE_TABLES_H
 
 #include <hb.h>
+#include <hb-ot.h>
 
 #include "XeTeX_ext.h"
 #include "XeTeXFontMgr.h"
diff --git a/Build/source/texk/web2c/xetexdir/XeTeXOTMath.cpp b/Build/source/texk/web2c/xetexdir/XeTeXOTMath.cpp
index a10cc21d236..d1a4ab432be 100644
--- a/Build/source/texk/web2c/xetexdir/XeTeXOTMath.cpp
+++ b/Build/source/texk/web2c/xetexdir/XeTeXOTMath.cpp
@@ -41,66 +41,33 @@ authorization from the copyright holders.
 #include "XeTeX_web.h"
 #include "XeTeXLayoutInterface.h"
 #include "XeTeXFontInst.h"
-#include "XeTeXswap.h"
-
-static int32_t getCoverage(const Coverage* coverage, GlyphID g)
-{
-    if (SWAP(coverage->format) == 1) {
-        const CoverageFormat1 *table = (const CoverageFormat1 *) coverage;
-        for (int i = 0; i < SWAP(table->glyphCount); i++) {
-            if (SWAP(table->glyphArray[i]) == g)
-                return i;
-        }
-    } else if (SWAP(coverage->format) == 2) {
-        const CoverageFormat2 *table = (const CoverageFormat2 *) coverage;
-        for (int i = 0; i < SWAP(table->rangeCount); i++) {
-            if (SWAP(table->rangeArray[i].start) <= g && SWAP(table->rangeArray[i].end) >= g)
-                return SWAP(table->rangeArray[i].startCoverageIndex) + (g - SWAP(table->rangeArray[i].start));
-        }
-    }
-
-    return -1;
-}
-
-static int16_t getMathConstant(XeTeXFontInst* fontInst, mathConstantIndex whichConstant)
-{
-    const char* table = fontInst->getMathTable();
-    if (table == NULL)
-        return 0;
-
-    const uint16_t* constants = (const uint16_t*)(table + SWAP(((const MathTableHeader*)table)->mathConstants));
-
-    if (whichConstant < firstMathValueRecord) {
-        /* it's a simple 16-bit value */
-        return SWAP(constants[whichConstant]);
-    }
-    else if (whichConstant <= lastMathValueRecord) {
-        const MathValueRecord* valueRecords = (const MathValueRecord*)
-            ((char*)constants + firstMathValueRecord * sizeof(uint16_t) - firstMathValueRecord * sizeof(MathValueRecord));
-        return SWAP(valueRecords[whichConstant].value);
-    }
-    else if (whichConstant <= lastMathConstant) {
-        return SWAP(constants[whichConstant + (lastMathValueRecord - firstMathValueRecord + 1)]);
-    }
-    else
-        return 0; /* or abort, with "internal error" or something */
-}
 
 int
 get_ot_math_constant(int f, int n)
 {
-    int rval = 0;
+    hb_ot_math_constant_t constant = (hb_ot_math_constant_t) n;
+    hb_position_t rval = 0;
 
     if (fontarea[f] == OTGR_FONT_FLAG) {
         XeTeXFontInst*  font = (XeTeXFontInst*)getFont((XeTeXLayoutEngine)fontlayoutengine[f]);
-        rval = getMathConstant(font, (mathConstantIndex)n);
+        hb_font_t* hbFont = font->getHbFont();
+        rval = hb_ot_math_get_constant(hbFont, constant);
         /* scale according to font size, except the ones that are percentages */
-        if (n > scriptScriptPercentScaleDown && n < radicalDegreeBottomRaisePercent)
-            rval = D2Fix(font->unitsToPoints(rval));
+        switch (constant) {
+            case HB_OT_MATH_CONSTANT_SCRIPT_PERCENT_SCALE_DOWN:
+            case HB_OT_MATH_CONSTANT_SCRIPT_SCRIPT_PERCENT_SCALE_DOWN:
+            case HB_OT_MATH_CONSTANT_RADICAL_DEGREE_BOTTOM_RAISE_PERCENT:
+                break;
+            default:
+                rval = D2Fix(font->unitsToPoints(rval));
+                break;
+        }
     }
     return rval;
 }
 
+#define unknown ((hb_ot_math_constant_t)-1)
+
 /* fontdimen IDs for math symbols font (family 2) */
 #define math_x_height   5
 #define math_quad       6
@@ -120,30 +87,30 @@ get_ot_math_constant(int f, int n)
 #define delim2          21  /* size of \.{\\atopwithdelims} delimiters in non-displays */
 #define axis_height     22  /* height of fraction lines above the baseline */
 
-const mathConstantIndex TeX_sym_to_OT_map[] = {
+const hb_ot_math_constant_t TeX_sym_to_OT_map[] = {
     unknown,
     unknown,
     unknown,
     unknown,
     unknown,
-    accentBaseHeight, // x-height
+    HB_OT_MATH_CONSTANT_ACCENT_BASE_HEIGHT, // x-height
     unknown, // quad
     unknown,
-    fractionNumeratorDisplayStyleShiftUp,
-    fractionNumeratorShiftUp,
-    stackTopShiftUp,
-    fractionDenominatorDisplayStyleShiftDown,
-    fractionDenominatorShiftDown,
-    superscriptShiftUp, // ??
-    superscriptShiftUp, // ??
-    superscriptShiftUpCramped,
-    subscriptShiftDown, // ??
-    subscriptShiftDown, // ??
-    superscriptBaselineDropMax, // ??
-    subscriptBaselineDropMin, // ??
-    delimitedSubFormulaMinHeight,
+    HB_OT_MATH_CONSTANT_FRACTION_NUMERATOR_DISPLAY_STYLE_SHIFT_UP,
+    HB_OT_MATH_CONSTANT_FRACTION_NUMERATOR_SHIFT_UP,
+    HB_OT_MATH_CONSTANT_STACK_TOP_SHIFT_UP,
+    HB_OT_MATH_CONSTANT_FRACTION_DENOMINATOR_DISPLAY_STYLE_SHIFT_DOWN,
+    HB_OT_MATH_CONSTANT_FRACTION_DENOMINATOR_SHIFT_DOWN,
+    HB_OT_MATH_CONSTANT_SUPERSCRIPT_SHIFT_UP, // ??
+    HB_OT_MATH_CONSTANT_SUPERSCRIPT_SHIFT_UP, // ??
+    HB_OT_MATH_CONSTANT_SUPERSCRIPT_SHIFT_UP_CRAMPED,
+    HB_OT_MATH_CONSTANT_SUBSCRIPT_SHIFT_DOWN, // ??
+    HB_OT_MATH_CONSTANT_SUBSCRIPT_SHIFT_DOWN, // ??
+    HB_OT_MATH_CONSTANT_SUPERSCRIPT_BASELINE_DROP_MAX, // ??
+    HB_OT_MATH_CONSTANT_SUBSCRIPT_BASELINE_DROP_MIN, // ??
+    HB_OT_MATH_CONSTANT_DELIMITED_SUB_FORMULA_MIN_HEIGHT,
     unknown, // using quad instead for now
-    axisHeight
+    HB_OT_MATH_CONSTANT_AXIS_HEIGHT
 };
 
 int
@@ -159,8 +126,8 @@ get_native_mathsy_param(int f, int n)
         rval = std::min<int>(1.5 * fontsize[f], get_native_mathsy_param(f, delim1));
     }
     else {
-        if (n < sizeof(TeX_sym_to_OT_map) / sizeof(mathConstantIndex)) {
-            mathConstantIndex ot_index = TeX_sym_to_OT_map[n];
+        if (n < sizeof(TeX_sym_to_OT_map) / sizeof(hb_ot_math_constant_t)) {
+            hb_ot_math_constant_t ot_index = TeX_sym_to_OT_map[n];
             if (ot_index != unknown)
                 rval = get_ot_math_constant(f, (int)ot_index);
         }
@@ -178,21 +145,21 @@ get_native_mathsy_param(int f, int n)
 #define big_op_spacing4         12  /* minimum baselineskip below displayed op */
 #define big_op_spacing5         13  /* padding above and below displayed limits */
 
-const mathConstantIndex TeX_ext_to_OT_map[] = {
+const hb_ot_math_constant_t TeX_ext_to_OT_map[] = {
     unknown,
     unknown,
     unknown,
     unknown,
     unknown,
-    accentBaseHeight, // x-height
+    HB_OT_MATH_CONSTANT_ACCENT_BASE_HEIGHT, // x-height
     unknown, // quad
     unknown,
-    fractionRuleThickness, // default_rule_thickness
-    upperLimitGapMin, // big_op_spacing1
-    lowerLimitGapMin, // big_op_spacing2
-    upperLimitBaselineRiseMin, // big_op_spacing3
-    lowerLimitBaselineDropMin, // big_op_spacing4
-    stackGapMin // big_op_spacing5
+    HB_OT_MATH_CONSTANT_FRACTION_RULE_THICKNESS, // default_rule_thickness
+    HB_OT_MATH_CONSTANT_UPPER_LIMIT_GAP_MIN, // big_op_spacing1
+    HB_OT_MATH_CONSTANT_LOWER_LIMIT_GAP_MIN, // big_op_spacing2
+    HB_OT_MATH_CONSTANT_UPPER_LIMIT_BASELINE_RISE_MIN, // big_op_spacing3
+    HB_OT_MATH_CONSTANT_LOWER_LIMIT_BASELINE_DROP_MIN, // big_op_spacing4
+    HB_OT_MATH_CONSTANT_STACK_GAP_MIN // big_op_spacing5
 };
 
 int
@@ -203,8 +170,8 @@ get_native_mathex_param(int f, int n)
     if (n == math_quad)
         rval = fontsize[f];
     else {
-        if (n < sizeof(TeX_ext_to_OT_map) / sizeof(mathConstantIndex)) {
-            mathConstantIndex ot_index = TeX_ext_to_OT_map[n];
+        if (n < sizeof(TeX_ext_to_OT_map) / sizeof(hb_ot_math_constant_t)) {
+            hb_ot_math_constant_t ot_index = TeX_ext_to_OT_map[n];
             if (ot_index != unknown)
                 rval = get_ot_math_constant(f, (int)ot_index);
         }
@@ -217,42 +184,25 @@ get_native_mathex_param(int f, int n)
 int
 get_ot_math_variant(int f, int g, int v, integer* adv, int horiz)
 {
-    int rval = g;
+    hb_codepoint_t rval = g;
     *adv = -1;
 
     if (fontarea[f] == OTGR_FONT_FLAG) {
         XeTeXFontInst*  font = (XeTeXFontInst*)getFont((XeTeXLayoutEngine)fontlayoutengine[f]);
-
-        const char* table = font->getMathTable();
-        if (table == NULL)
-            return rval;
-
-        uint16_t    offset = SWAP(((const MathTableHeader*)table)->mathVariants);
-        if (offset == 0)
-            return rval;
-        const MathVariants* variants = (const MathVariants*)(table + offset);
-
-        offset = horiz ? SWAP(variants->horizGlyphCoverage) : SWAP(variants->vertGlyphCoverage);
-        if (offset == 0)
-            return rval;
-        const Coverage* coverage = (const Coverage*)(((const char*)variants) + offset);
-
-        int32_t index = getCoverage(coverage, g);
-        if (index >= 0) {
-            if (horiz)
-                index += SWAP(variants->vertGlyphCount);
-            const MathGlyphConstruction*    construction = (const MathGlyphConstruction*)(((const char*)variants)
-                                                            + SWAP(variants->vertGlyphConstruction[index]));
-            if (v < SWAP(construction->variantCount)) {
-                rval = SWAP(construction->mathGlyphVariantRecord[v].variantGlyph);
-                *adv = D2Fix(font->unitsToPoints(SWAP(construction->mathGlyphVariantRecord[v].advanceMeasurement)));
-            }
+        hb_font_t* hbFont = font->getHbFont();
+        hb_ot_math_glyph_variant_t variant[1];
+        unsigned int count = 1;
+        hb_ot_math_get_glyph_variants(hbFont, g, horiz ? HB_DIRECTION_RTL : HB_DIRECTION_TTB, v, &count, variant);
+        if (count > 0) {
+            rval = variant->glyph;
+            *adv = D2Fix(font->unitsToPoints(variant->advance));
         }
     }
 
     return rval;
 }
 
+
 void*
 get_ot_assembly_ptr(int f, int g, int horiz)
 {
@@ -260,66 +210,40 @@ get_ot_assembly_ptr(int f, int g, int horiz)
 
     if (fontarea[f] == OTGR_FONT_FLAG) {
         XeTeXFontInst*  font = (XeTeXFontInst*)getFont((XeTeXLayoutEngine)fontlayoutengine[f]);
-
-        const char* table = font->getMathTable();
-        if (table == NULL)
-            return rval;
-
-        uint16_t    offset = SWAP(((const MathTableHeader*)table)->mathVariants);
-        if (offset == 0)
-            return rval;
-        const MathVariants* variants = (const MathVariants*)(table + offset);
-
-        offset = horiz ? SWAP(variants->horizGlyphCoverage) : SWAP(variants->vertGlyphCoverage);
-        if (offset == 0)
-            return rval;
-        const Coverage* coverage = (const Coverage*)(((const char*)variants) + offset);
-
-        int32_t index = getCoverage(coverage, g);
-        if (index >= 0) {
-            if (horiz)
-                index += SWAP(variants->vertGlyphCount);
-            const MathGlyphConstruction*    construction = (const MathGlyphConstruction*)(((const char*)variants)
-                                                            + SWAP(variants->vertGlyphConstruction[index]));
-            offset = SWAP(construction->glyphAssembly);
-            if (offset != 0)
-                rval = (void*)(((const char*)construction) + offset);
+        hb_font_t* hbFont = font->getHbFont();
+
+        unsigned int count = hb_ot_math_get_glyph_assembly(hbFont, g, horiz ? HB_DIRECTION_RTL : HB_DIRECTION_TTB, 0, NULL, NULL, NULL);
+        if (count > 0) {
+            GlyphAssembly* a = (GlyphAssembly*) xmalloc(sizeof(GlyphAssembly));
+            a->count = count;
+            a->parts = (hb_ot_math_glyph_part_t*) xmalloc(count * sizeof(hb_ot_math_glyph_part_t));
+            hb_ot_math_get_glyph_assembly(hbFont, g, horiz ? HB_DIRECTION_RTL : HB_DIRECTION_TTB, 0, &a->count, a->parts, NULL);
+            rval = (void*) a;
         }
     }
 
     return rval;
 }
 
+void
+free_ot_assembly(GlyphAssembly* a)
+{
+    if (!a)
+        return;
+    free (a->parts);
+    free (a);
+}
+
 int
 get_ot_math_ital_corr(int f, int g)
 {
-    int rval = 0;
+    hb_position_t rval = 0;
 
     if (fontarea[f] == OTGR_FONT_FLAG) {
         XeTeXFontInst*  font = (XeTeXFontInst*)getFont((XeTeXLayoutEngine)fontlayoutengine[f]);
-
-        const char* table = font->getMathTable();
-        if (table == NULL)
-            return rval;
-
-        uint16_t    offset = SWAP(((const MathTableHeader*)table)->mathGlyphInfo);
-        if (offset == 0)
-            return rval;
-        const MathGlyphInfo* glyphInfo = (const MathGlyphInfo*)(table + offset);
-
-        offset = SWAP(glyphInfo->mathItalicsCorrectionInfo);
-        if (offset == 0)
-            return rval;
-        const MathItalicsCorrectionInfo* italCorrInfo = (const MathItalicsCorrectionInfo*)(((const char*)glyphInfo) + offset);
-
-        offset = SWAP(italCorrInfo->coverage);
-        if (offset == 0)
-            return rval;
-        const Coverage* coverage = (const Coverage*)(((const char*)italCorrInfo) + offset);
-
-        int32_t index = getCoverage(coverage, g);
-        if (index >= 0 && index < SWAP(italCorrInfo->italicsCorrectionCount))
-            rval = D2Fix(font->unitsToPoints(SWAP(italCorrInfo->italicsCorrection[index].value)));
+        hb_font_t* hbFont = font->getHbFont();
+        rval = hb_ot_math_get_glyph_italics_correction(hbFont, g);
+        rval = D2Fix(font->unitsToPoints(rval));
     }
 
     return rval;
@@ -328,35 +252,13 @@ get_ot_math_ital_corr(int f, int g)
 int
 get_ot_math_accent_pos(int f, int g)
 {
-    int rval = 0x7fffffffUL;
+    hb_position_t rval = 0x7fffffffUL;
 
     if (fontarea[f] == OTGR_FONT_FLAG) {
         XeTeXFontInst*  font = (XeTeXFontInst*)getFont((XeTeXLayoutEngine)fontlayoutengine[f]);
-
-        const char* table = font->getMathTable();
-        if (table == NULL)
-            return rval;
-
-        uint16_t    offset = SWAP(((const MathTableHeader*)table)->mathGlyphInfo);
-        if (offset == 0)
-            return rval;
-        const MathGlyphInfo* glyphInfo = (const MathGlyphInfo*)(table + offset);
-
-        offset = SWAP(glyphInfo->mathTopAccentAttachment);
-        if (offset == 0)
-            return rval;
-        const MathTopAccentAttachment* accentAttachment = (const MathTopAccentAttachment*)(((const char*)glyphInfo) + offset);
-
-        offset = SWAP(accentAttachment->coverage);
-        if (offset == 0)
-            return rval;
-        const Coverage* coverage = (const Coverage*)(((const char*)accentAttachment) + offset);
-
-        int32_t index = getCoverage(coverage, g);
-        if (index >= 0 && index < SWAP(accentAttachment->topAccentAttachmentCount)) {
-            rval = (int16_t)SWAP(accentAttachment->topAccentAttachment[index].value);
-            rval = D2Fix(font->unitsToPoints(rval));
-        }
+        hb_font_t* hbFont = font->getHbFont();
+        rval = hb_ot_math_get_glyph_top_accent_attachment(hbFont, g);
+        rval = D2Fix(font->unitsToPoints(rval));
     }
 
     return rval;
@@ -365,97 +267,27 @@ get_ot_math_accent_pos(int f, int g)
 int
 ot_min_connector_overlap(int f)
 {
-    int rval = 0;
+    hb_position_t rval = 0;
 
     if (fontarea[f] == OTGR_FONT_FLAG) {
         XeTeXFontInst*  font = (XeTeXFontInst*)getFont((XeTeXLayoutEngine)fontlayoutengine[f]);
-
-        const char* table = font->getMathTable();
-        if (table == NULL)
-            return rval;
-
-        uint16_t    offset = SWAP(((const MathTableHeader*)table)->mathVariants);
-        if (offset == 0)
-            return rval;
-        const MathVariants* variants = (const MathVariants*)(table + offset);
-
-        rval = D2Fix(font->unitsToPoints(SWAP(variants->minConnectorOverlap)));
+        hb_font_t* hbFont = font->getHbFont();
+        rval = hb_ot_math_get_min_connector_overlap(hbFont, HB_DIRECTION_RTL);
+        rval = D2Fix(font->unitsToPoints(rval));
     }
 
     return rval;
 }
 
-typedef enum {
-    topRight,
-    topLeft,
-    bottomRight,
-    bottomLeft,
-} MathKernSide;
-
 static int
-getMathKernAt(int f, int g, MathKernSide side, int height)
+getMathKernAt(int f, int g, hb_ot_math_kern_t side, int height)
 {
-    int rval = 0;
+    hb_position_t rval = 0;
+
     if (fontarea[f] == OTGR_FONT_FLAG) {
         XeTeXFontInst* font = (XeTeXFontInst*)getFont((XeTeXLayoutEngine)fontlayoutengine[f]);
-
-        const char* table = font->getMathTable();
-        if (table == NULL)
-            return rval;
-
-        uint16_t    offset = SWAP(((const MathTableHeader*)table)->mathGlyphInfo);
-        if (offset == 0)
-            return rval;
-
-        const MathGlyphInfo* glyphInfo = (const MathGlyphInfo*)(table + offset);
-
-        offset = SWAP(glyphInfo->mathKernInfo);
-        if (offset == 0)
-            return rval;
-
-        const MathKernInfo* mathKernInfo = (const MathKernInfo*)(((const char*)glyphInfo) + offset);
-
-        offset = SWAP(mathKernInfo->coverage);
-        if (offset == 0)
-            return rval;
-
-        const Coverage* coverage = (const Coverage*)(((const char*)mathKernInfo) + offset);
-
-        int32_t index = getCoverage(coverage, g);
-        if (index >= 0 && index < SWAP(mathKernInfo->kernInfoCount)) {
-            if (side == topRight)
-                offset = SWAP(mathKernInfo->kernInfo[index].topRight);
-            else if (side == bottomRight)
-                offset = SWAP(mathKernInfo->kernInfo[index].bottomRight);
-            else if (side == topLeft)
-                offset = SWAP(mathKernInfo->kernInfo[index].topLeft);
-            else if (side == bottomLeft)
-                offset = SWAP(mathKernInfo->kernInfo[index].bottomLeft);
-            else
-                assert(0); // we should not reach here
-
-            if (offset == 0)
-                return rval;
-
-            const MathKernTable* kernTable = (const MathKernTable*)(((const char*)mathKernInfo) + offset);
-
-            uint16_t count = SWAP(kernTable->heightCount);
-
-            // kern[] array immediately follows the height[] array with |count| elements
-            const MathValueRecord* kern = &kernTable->height[0] + count;
-
-            if (count == 0 || height < SWAP(kernTable->height[0].value))
-                rval = SWAP(kern[0].value);
-            else {
-                rval = SWAP(kern[count].value);
-                for (int i = 0; i < count; i++) {
-                    if (height <= SWAP(kernTable->height[i].value)) {
-                        rval = SWAP(kern[i].value);
-                        break;
-                    }
-                }
-            }
-        }
+        hb_font_t* hbFont = font->getHbFont();
+        rval = hb_ot_math_get_glyph_kerning(hbFont, g, side, height);
     }
 
     return rval;
@@ -505,12 +337,12 @@ get_ot_math_kern(int f, int g, int sf, int sg, int cmd, int shift)
             corr_height_top =  font->pointsToUnits(glyph_height(f, g));
             corr_height_bot = -font->pointsToUnits(glyph_depth(sf, sg) + Fix2D(shift));
 
-            kern = getMathKernAt(f, g, topRight, corr_height_top);
-            skern = getMathKernAt(sf, sg, bottomLeft, corr_height_top);
+            kern = getMathKernAt(f, g, HB_OT_MATH_KERN_TOP_RIGHT, corr_height_top);
+            skern = getMathKernAt(sf, sg, HB_OT_MATH_KERN_BOTTOM_LEFT, corr_height_top);
             rval = kern + skern;
 
-            kern = getMathKernAt(f, g, topRight, corr_height_bot);
-            skern = getMathKernAt(sf, sg, bottomLeft, corr_height_bot);
+            kern = getMathKernAt(f, g, HB_OT_MATH_KERN_TOP_RIGHT, corr_height_bot);
+            skern = getMathKernAt(sf, sg, HB_OT_MATH_KERN_BOTTOM_LEFT, corr_height_bot);
             if ((kern + skern) < rval)
                 rval = kern + skern;
 
@@ -518,12 +350,12 @@ get_ot_math_kern(int f, int g, int sf, int sg, int cmd, int shift)
             corr_height_top =  font->pointsToUnits(glyph_height(sf, sg) - Fix2D(shift));
             corr_height_bot = -font->pointsToUnits(glyph_depth(f, g));
 
-            kern = getMathKernAt(f, g, bottomRight, corr_height_top);
-            skern = getMathKernAt(sf, sg, topLeft, corr_height_top);
+            kern = getMathKernAt(f, g, HB_OT_MATH_KERN_BOTTOM_RIGHT, corr_height_top);
+            skern = getMathKernAt(sf, sg, HB_OT_MATH_KERN_TOP_LEFT, corr_height_top);
             rval = kern + skern;
 
-            kern = getMathKernAt(f, g, bottomRight, corr_height_bot);
-            skern = getMathKernAt(sf, sg, topLeft, corr_height_bot);
+            kern = getMathKernAt(f, g, HB_OT_MATH_KERN_BOTTOM_RIGHT, corr_height_bot);
+            skern = getMathKernAt(sf, sg, HB_OT_MATH_KERN_TOP_LEFT, corr_height_bot);
             if ((kern + skern) < rval)
                 rval = kern + skern;
 
@@ -540,19 +372,19 @@ get_ot_math_kern(int f, int g, int sf, int sg, int cmd, int shift)
 int
 ot_part_count(const GlyphAssembly* a)
 {
-    return SWAP(a->partCount);
+    return a->count;
 }
 
 int
 ot_part_glyph(const GlyphAssembly* a, int i)
 {
-    return SWAP(a->partRecords[i].glyph);
+    return a->parts[i].glyph;
 }
 
 int
 ot_part_is_extender(const GlyphAssembly* a, int i)
 {
-    return (SWAP(a->partRecords[i].partFlags) & fExtender) != 0;
+    return (a->parts[i].flags & HB_MATH_GLYPH_PART_FLAG_EXTENDER) != 0;
 }
 
 int
@@ -562,7 +394,7 @@ ot_part_start_connector(int f, const GlyphAssembly* a, int i)
 
     if (fontarea[f] == OTGR_FONT_FLAG) {
         XeTeXFontInst*  font = (XeTeXFontInst*)getFont((XeTeXLayoutEngine)fontlayoutengine[f]);
-        rval = D2Fix(font->unitsToPoints(SWAP(a->partRecords[i].startConnectorLength)));
+        rval = D2Fix(font->unitsToPoints(a->parts[i].start_connector_length));
     }
 
     return rval;
@@ -575,7 +407,7 @@ ot_part_end_connector(int f, const GlyphAssembly* a, int i)
 
     if (fontarea[f] == OTGR_FONT_FLAG) {
         XeTeXFontInst*  font = (XeTeXFontInst*)getFont((XeTeXLayoutEngine)fontlayoutengine[f]);
-        rval = D2Fix(font->unitsToPoints(SWAP(a->partRecords[i].endConnectorLength)));
+        rval = D2Fix(font->unitsToPoints(a->parts[i].end_connector_length));
     }
 
     return rval;
@@ -588,7 +420,7 @@ ot_part_full_advance(int f, const GlyphAssembly* a, int i)
 
     if (fontarea[f] == OTGR_FONT_FLAG) {
         XeTeXFontInst*  font = (XeTeXFontInst*)getFont((XeTeXLayoutEngine)fontlayoutengine[f]);
-        rval = D2Fix(font->unitsToPoints(SWAP(a->partRecords[i].fullAdvance)));
+        rval = D2Fix(font->unitsToPoints(a->parts[i].full_advance));
     }
 
     return rval;
diff --git a/Build/source/texk/web2c/xetexdir/XeTeXOTMath.h b/Build/source/texk/web2c/xetexdir/XeTeXOTMath.h
index ba2cc873041..1b8362bb0ea 100644
--- a/Build/source/texk/web2c/xetexdir/XeTeXOTMath.h
+++ b/Build/source/texk/web2c/xetexdir/XeTeXOTMath.h
@@ -34,7 +34,11 @@ authorization from the copyright holders.
 #define __XETEX_OT_MATH__
 
 #include "XeTeX_ext.h"
-#include "MathTable.h"
+
+typedef struct {
+      unsigned int             count;
+      hb_ot_math_glyph_part_t* parts;
+} GlyphAssembly;
 
 /* public "C" APIs for calling from Web(-to-C) code */
 #ifdef __cplusplus
@@ -45,6 +49,7 @@ extern "C" {
     int get_ot_math_constant(int f, int n);
     int get_ot_math_variant(int f, int g, int v, integer* adv, int horiz);
     void* get_ot_assembly_ptr(int f, int g, int horiz);
+    void free_ot_assembly(GlyphAssembly* a);
     int get_ot_math_ital_corr(int f, int g);
     int get_ot_math_accent_pos(int f, int g);
     int get_ot_math_kern(int f, int g, int sf, int sg, int cmd, int shift);
diff --git a/Build/source/texk/web2c/xetexdir/am/xetex.am b/Build/source/texk/web2c/xetexdir/am/xetex.am
index d3a0def8320..475f8dc44bc 100644
--- a/Build/source/texk/web2c/xetexdir/am/xetex.am
+++ b/Build/source/texk/web2c/xetexdir/am/xetex.am
@@ -135,7 +135,6 @@ libxetex_a_CXXFLAGS = # $(WARNING_CXXFLAGS)
 libxetex_a_OBJCXXFLAGS = # $(WARNING_OBJCXXFLAGS)
 
 libxetex_a_SOURCES = \
-	xetexdir/MathTable.h \
 	xetexdir/XeTeXFontInst.cpp \
 	xetexdir/XeTeXFontInst.h \
 	xetexdir/XeTeXFontMgr.cpp \
diff --git a/Build/source/texk/web2c/xetexdir/xetex.defines b/Build/source/texk/web2c/xetexdir/xetex.defines
index ef22d53c8db..8772a82b622 100644
--- a/Build/source/texk/web2c/xetexdir/xetex.defines
+++ b/Build/source/texk/web2c/xetexdir/xetex.defines
@@ -113,6 +113,7 @@ authorization from the copyright holders.
 @define function getotmathconstant();
 @define function getotmathvariant();
 @define function getotassemblyptr();
+@define procedure freeotassembly();
 @define function getotmathitalcorr();
 @define function getotmathaccentpos();
 @define function getotmathkern();
diff --git a/Build/source/texk/web2c/xetexdir/xetex.h b/Build/source/texk/web2c/xetexdir/xetex.h
index 8231d768043..2360e3920ca 100644
--- a/Build/source/texk/web2c/xetexdir/xetex.h
+++ b/Build/source/texk/web2c/xetexdir/xetex.h
@@ -91,6 +91,7 @@ authorization from the copyright holders.
 #define getotmathconstant                       get_ot_math_constant
 #define getotmathvariant                        get_ot_math_variant
 #define getotassemblyptr                        get_ot_assembly_ptr
+#define freeotassembly                          free_ot_assembly
 #define getotmathitalcorr                       get_ot_math_ital_corr
 #define getotmathaccentpos                      get_ot_math_accent_pos
 #define getotmathkern                           get_ot_math_kern
diff --git a/Build/source/texk/web2c/xetexdir/xetex.web b/Build/source/texk/web2c/xetexdir/xetex.web
index 227ab66bb18..b935cefe947 100644
--- a/Build/source/texk/web2c/xetexdir/xetex.web
+++ b/Build/source/texk/web2c/xetexdir/xetex.web
@@ -16435,6 +16435,7 @@ end else  begin b:=new_null_box;
   width(b):=null_delimiter_space; {use this width if no delimiter was found}
   end;
 shift_amount(b):=half(height(b)-depth(b)) - axis_height(s);
+free_ot_assembly(ot_assembly_ptr);
 var_delimiter:=b;
 end;
 
@@ -17083,6 +17084,7 @@ var p,@!x,@!y:pointer; {temporary registers for box construction}
 @!ot_assembly_ptr:void_pointer;
 begin fetch(accent_chr(q));
 x:=null;
+ot_assembly_ptr:=nil;
 if is_native_font(cur_f) then
   begin c:=cur_c; f:=cur_f;
   if not is_bottom_acc(q) then s:=compute_ot_math_accent_pos(q) else s:=0;
@@ -17136,6 +17138,7 @@ if x<>null then begin
   info(nucleus(q)):=y;
   math_type(nucleus(q)):=sub_box;
   end;
+  free_ot_assembly(ot_assembly_ptr);
 end;
 
 @ @<Make the height of box |y|...@>=
@@ -17347,6 +17350,7 @@ var delta:scaled; {offset between subscript and superscript}
 begin if (subtype(q)=normal)and(cur_style<text_style) then
   subtype(q):=limits;
 delta:=0;
+ot_assembly_ptr:=nil;
 if math_type(nucleus(q))=math_char then
   begin fetch(nucleus(q));
   if not is_ot_font(cur_f) then begin
@@ -17404,6 +17408,7 @@ found:
 save_f:=cur_f;
 if subtype(q)=limits then
   @<Construct a box with limits above and below it, skewed by |delta|@>;
+free_ot_assembly(ot_assembly_ptr);
 make_op:=delta;
 end;