Fixes JavaScriptCore on musl platforms, taken and reformatted from the Gentoo
musl overlay:

https://gitweb.gentoo.org/proj/musl.git/tree/net-libs/webkit-gtk/files/webkit-gtk-2.18.1-musl.patch

--- a/Source/JavaScriptCore/runtime/MachineContext.h
+++ b/Source/JavaScriptCore/runtime/MachineContext.h
@@ -146,7 +146,7 @@ inline void*& stackPointer(mcontext_t& machineContext)
 #error Unknown Architecture
 #endif
 
-#elif defined(__GLIBC__) || defined(__BIONIC__)
+#elif defined(__linux__)
 
 #if CPU(X86)
     return reinterpret_cast<void*&>((uintptr_t&) machineContext.gregs[REG_ESP]);
@@ -251,7 +251,7 @@ inline void*& framePointer(mcontext_t& machineContext)
 #error Unknown Architecture
 #endif
 
-#elif defined(__GLIBC__) || defined(__BIONIC__)
+#elif defined(__linux__)
 
 // The following sequence depends on glibc's sys/ucontext.h.
 #if CPU(X86)
@@ -354,7 +354,7 @@ inline void*& instructionPointer(mcontext_t& machineContext)
 #error Unknown Architecture
 #endif
 
-#elif defined(__GLIBC__) || defined(__BIONIC__)
+#elif defined(__linux__)
 
 // The following sequence depends on glibc's sys/ucontext.h.
 #if CPU(X86)
@@ -466,7 +466,7 @@ inline void*& argumentPointer<1>(mcontext_t& machineContext)
 #error Unknown Architecture
 #endif
 
-#elif defined(__GLIBC__) || defined(__BIONIC__)
+#elif defined(__linux__)
 
 // The following sequence depends on glibc's sys/ucontext.h.
 #if CPU(X86)
@@ -583,7 +583,7 @@ inline void*& llintInstructionPointer(mcontext_t& machineContext)
 #error Unknown Architecture
 #endif
 
-#elif defined(__GLIBC__) || defined(__BIONIC__)
+#elif defined(__linux__)
 
 // The following sequence depends on glibc's sys/ucontext.h.
 #if CPU(X86)
 
--- a/Source/JavaScriptCore/runtime/Options.h
+++ b/Source/JavaScriptCore/runtime/Options.h
@@ -126,9 +126,9 @@
     \
     v(bool, reportMustSucceedExecutableAllocations, false, Normal, nullptr) \
     \
-    v(unsigned, maxPerThreadStackUsage, 4 * MB, Normal, "Max allowed stack usage by the VM") \
-    v(unsigned, softReservedZoneSize, 128 * KB, Normal, "A buffer greater than reservedZoneSize that reserves space for stringifying exceptions.") \
-    v(unsigned, reservedZoneSize, 64 * KB, Normal, "The amount of stack space we guarantee to our clients (and to interal VM code that does not call out to clients).") \
+    v(unsigned, maxPerThreadStackUsage, 80 * KB, Normal, "Max allowed stack usage by the VM") \
+    v(unsigned, softReservedZoneSize, 32 * KB, Normal, "A buffer greater than reservedZoneSize that reserves space for stringifying exceptions.") \
+    v(unsigned, reservedZoneSize, 16 * KB, Normal, "The amount of stack space we guarantee to our clients (and to interal VM code that does not call out to clients).") \
     \
     v(bool, crashIfCantAllocateJITMemory, false, Normal, nullptr) \
     v(unsigned, jitMemoryReservationSize, 0, Normal, "Set this number to change the executable allocation size in ExecutableAllocatorFixedVMPool. (In bytes.)") \

--- a/Source/ThirdParty/ANGLE/src/compiler/preprocessor/ExpressionParser.cpp
+++ b/Source/ThirdParty/ANGLE/src/compiler/preprocessor/ExpressionParser.cpp
@@ -836,7 +836,7 @@
 #if YYERROR_VERBOSE
 
 # ifndef yystrlen
-#  if defined __GLIBC__ && defined _STRING_H
+#  if defined __linux__ && defined _STRING_H
 #   define yystrlen strlen
 #  else
 /* Return the length of YYSTR.  */
@@ -852,7 +852,7 @@
 # endif
 
 # ifndef yystpcpy
-#  if defined __GLIBC__ && defined _STRING_H && defined _GNU_SOURCE
+#  if defined __linux__ && defined _STRING_H && defined _GNU_SOURCE
 #   define yystpcpy stpcpy
 #  else
 /* Copy YYSRC to YYDEST, returning the address of the terminating '\0' in

--- a/Source/ThirdParty/ANGLE/src/compiler/translator/glslang_tab.cpp
+++ b/Source/ThirdParty/ANGLE/src/compiler/translator/glslang_tab.cpp
@@ -1975,7 +1975,7 @@
 #if YYERROR_VERBOSE
 
 # ifndef yystrlen
-#  if defined __GLIBC__ && defined _STRING_H
+#  if defined __linux__ && defined _STRING_H
 #   define yystrlen strlen
 #  else
 /* Return the length of YYSTR.  */
@@ -1991,7 +1991,7 @@
 # endif
 
 # ifndef yystpcpy
-#  if defined __GLIBC__ && defined _STRING_H && defined _GNU_SOURCE
+#  if defined __linux__ && defined _STRING_H && defined _GNU_SOURCE
 #   define yystpcpy stpcpy
 #  else
 /* Copy YYSRC to YYDEST, returning the address of the terminating '\0' in

--- a/Source/WTF/wtf/Platform.h
+++ b/Source/WTF/wtf/Platform.h
@@ -679,7 +679,7 @@
 #define HAVE_CFNETWORK_STORAGE_PARTITIONING 1
 #endif
 
-#if OS(DARWIN) || ((OS(FREEBSD) || defined(__GLIBC__) || defined(__BIONIC__)) && (CPU(X86) || CPU(X86_64) || CPU(ARM) || CPU(ARM64) || CPU(MIPS)))
+#if OS(DARWIN) || ((OS(FREEBSD) || defined(__linux__)) && (CPU(X86) || CPU(X86_64) || CPU(ARM) || CPU(ARM64) || CPU(MIPS)))
 #define HAVE_MACHINE_CONTEXT 1
 #endif

--- a/Source/WebCore/xml/XPathGrammar.cpp
+++ b/Source/WebCore/xml/XPathGrammar.cpp
@@ -967,7 +967,7 @@
 #if YYERROR_VERBOSE
 
 # ifndef yystrlen
-#  if defined __GLIBC__ && defined _STRING_H
+#  if defined __linux__ && defined _STRING_H
 #   define yystrlen strlen
 #  else
 /* Return the length of YYSTR.  */
@@ -990,7 +990,7 @@
 # endif
 
 # ifndef yystpcpy
-#  if defined __GLIBC__ && defined _STRING_H && defined _GNU_SOURCE
+#  if defined __linux__ && defined _STRING_H && defined _GNU_SOURCE
 #   define yystpcpy stpcpy
 #  else
 /* Copy YYSRC to YYDEST, returning the address of the terminating '\0' in