1# 2# This file contains common settings used for building FreeBSD 3# sources. 4 5# Enable various levels of compiler warning checks. These may be 6# overridden (e.g. if using a non-gcc compiler) by defining MK_WARNS=no. 7 8# for GCC: https://gcc.gnu.org/onlinedocs/gcc/Warning-Options.html 9# for clang: https://clang.llvm.org/docs/DiagnosticsReference.html 10 11.include <bsd.compiler.mk> 12 13# the default is gnu99 for now 14CSTD?= gnu99 15 16.if ${CSTD} == "c89" || ${CSTD} == "c90" 17CFLAGS+= -std=iso9899:1990 18.elif ${CSTD} == "c94" || ${CSTD} == "c95" 19CFLAGS+= -std=iso9899:199409 20.elif ${CSTD} == "c99" 21CFLAGS+= -std=iso9899:1999 22.else # CSTD 23CFLAGS+= -std=${CSTD} 24.endif # CSTD 25 26.if !empty(CXXSTD) 27CXXFLAGS+= -std=${CXXSTD} 28.endif 29 30# This gives the Makefile we're evaluating at the top-level a chance to set 31# WARNS. If it doesn't do so, we may freely pull a DEFAULTWARNS if it's set 32# and use that. This allows us to default WARNS to 6 for src builds without 33# needing to set the default in various Makefile.inc. 34.if !defined(WARNS) && defined(DEFAULTWARNS) 35WARNS= ${DEFAULTWARNS} 36.endif 37 38# -pedantic is problematic because it also imposes namespace restrictions 39#CFLAGS+= -pedantic 40.if defined(WARNS) 41.if ${WARNS} >= 1 42CWARNFLAGS+= -Wsystem-headers 43.if ${MK_WERROR} != "no" && ${MK_WERROR.${COMPILER_TYPE}:Uyes} != "no" 44CWARNFLAGS+= -Werror 45.endif # ${MK_WERROR} != "no" && ${MK_WERROR.${COMPILER_TYPE}:Uyes} != "no" 46.endif # WARNS >= 1 47.if ${WARNS} >= 2 48CWARNFLAGS+= -Wall -Wno-format-y2k 49.endif # WARNS >= 2 50.if ${WARNS} >= 3 51CWARNFLAGS+= -W -Wno-unused-parameter 52.if ${COMPILER_TYPE} == "clang" 53CWARNFLAGS+= -Wstrict-prototypes 54.endif 55CWARNFLAGS+= -Wmissing-prototypes -Wpointer-arith 56.endif # WARNS >= 3 57.if ${WARNS} >= 4 58CWARNFLAGS+= -Wreturn-type -Wcast-qual -Wwrite-strings -Wswitch -Wshadow\ 59 -Wunused-parameter 60.if !defined(NO_WCAST_ALIGN) && !defined(NO_WCAST_ALIGN.${COMPILER_TYPE}) 61CWARNFLAGS+= -Wcast-align 62.endif # !NO_WCAST_ALIGN !NO_WCAST_ALIGN.${COMPILER_TYPE} 63.endif # WARNS >= 4 64.if ${WARNS} >= 6 65CWARNFLAGS+= -Wchar-subscripts -Wnested-externs \ 66 -Wold-style-definition 67.if !defined(NO_WMISSING_VARIABLE_DECLARATIONS) 68CWARNFLAGS.clang+= -Wmissing-variable-declarations 69.endif 70.if !defined(NO_WTHREAD_SAFETY) 71CWARNFLAGS.clang+= -Wthread-safety 72.endif 73.endif # WARNS >= 6 74.if ${WARNS} >= 2 && ${WARNS} <= 4 75# XXX Delete -Wuninitialized by default for now -- the compiler doesn't 76# XXX always get it right. 77CWARNFLAGS+= -Wno-uninitialized 78.endif # WARNS >=2 && WARNS <= 4 79CWARNFLAGS+= -Wno-pointer-sign 80.if !defined(NO_WDATE_TIME) 81CWARNFLAGS+= -Wdate-time 82.endif # NO_WDATE_TIME 83# Clang has more warnings enabled by default, and when using -Wall, so if WARNS 84# is set to low values, these have to be disabled explicitly. 85.if ${WARNS} <= 6 86CWARNFLAGS.clang+= -Wno-empty-body -Wno-string-plus-int 87CWARNFLAGS.clang+= -Wno-unused-const-variable 88.if ${COMPILER_TYPE} == "clang" && ${COMPILER_VERSION} >= 150000 89CWARNFLAGS.clang+= -Wno-error=unused-but-set-parameter 90.endif 91.if ${COMPILER_TYPE} == "clang" && ${COMPILER_VERSION} >= 190000 92# Similar to gcc >= 8.1 -Wno-error=cast-function-type below 93CWARNFLAGS.clang+= -Wno-error=cast-function-type-mismatch 94.endif 95.endif # WARNS <= 6 96.if ${WARNS} <= 3 97CWARNFLAGS.clang+= -Wno-tautological-compare -Wno-unused-value\ 98 -Wno-parentheses-equality -Wno-unused-function -Wno-enum-conversion 99CWARNFLAGS.clang+= -Wno-unused-local-typedef 100CWARNFLAGS.clang+= -Wno-address-of-packed-member 101.if ${COMPILER_TYPE} == "gcc" && ${COMPILER_VERSION} >= 90100 102CWARNFLAGS.gcc+= -Wno-address-of-packed-member 103.endif 104.endif # WARNS <= 3 105.if ${WARNS} <= 2 106CWARNFLAGS.clang+= -Wno-switch -Wno-switch-enum -Wno-knr-promoted-parameter 107.endif # WARNS <= 2 108.if ${WARNS} <= 1 109CWARNFLAGS.clang+= -Wno-parentheses 110.endif # WARNS <= 1 111.if defined(NO_WARRAY_BOUNDS) 112CWARNFLAGS.clang+= -Wno-array-bounds 113.endif # NO_WARRAY_BOUNDS 114.if defined(NO_WMISLEADING_INDENTATION) && \ 115 ((${COMPILER_TYPE} == "clang" && ${COMPILER_VERSION} >= 100000) || \ 116 ${COMPILER_TYPE} == "gcc") 117CWARNFLAGS+= -Wno-misleading-indentation 118.endif # NO_WMISLEADING_INDENTATION 119.if ${COMPILER_VERSION} >= 130000 120NO_WUNUSED_BUT_SET_VARIABLE= -Wno-unused-but-set-variable 121.endif 122.if ${COMPILER_TYPE} == "clang" && ${COMPILER_VERSION} >= 140000 123NO_WBITWISE_INSTEAD_OF_LOGICAL= -Wno-bitwise-instead-of-logical 124.endif 125.if ${COMPILER_TYPE} == "clang" && ${COMPILER_VERSION} >= 150000 126NO_WARRAY_PARAMETER= -Wno-array-parameter 127NO_WSTRICT_PROTOTYPES= -Wno-strict-prototypes 128NO_WDEPRECATED_NON_PROTOTYPE=-Wno-deprecated-non-prototype 129.endif 130.if ${COMPILER_TYPE} == "gcc" && ${COMPILER_VERSION} >= 50200 131NO_WUNUSED_BUT_SET_VARIABLE=-Wno-unused-but-set-variable 132.endif 133.if ${COMPILER_TYPE} == "gcc" && ${COMPILER_VERSION} >= 100100 134NO_WZERO_LENGTH_BOUNDS= -Wno-zero-length-bounds 135.endif 136.if ${COMPILER_TYPE} == "gcc" && ${COMPILER_VERSION} >= 110100 137NO_WARRAY_PARAMETER= -Wno-array-parameter 138.endif 139.if ${COMPILER_TYPE} == "gcc" && ${COMPILER_VERSION} >= 120100 140NO_WUSE_AFTER_FREE= -Wno-use-after-free 141NO_WDANGLING_POINTER= -Wno-dangling-pointer 142.endif 143.endif # WARNS 144 145.if defined(FORMAT_AUDIT) 146WFORMAT= 1 147.endif # FORMAT_AUDIT 148.if defined(WFORMAT) 149.if ${WFORMAT} > 0 150#CWARNFLAGS+= -Wformat-nonliteral -Wformat-security -Wno-format-extra-args 151CWARNFLAGS+= -Wformat=2 -Wno-format-extra-args 152.if ${WARNS:U0} <= 3 153CWARNFLAGS.clang+= -Wno-format-nonliteral 154.endif # WARNS <= 3 155.if ${MK_WERROR} != "no" && ${MK_WERROR.${COMPILER_TYPE}:Uyes} != "no" 156CWARNFLAGS+= -Werror 157.endif # ${MK_WERROR} != "no" && ${MK_WERROR.${COMPILER_TYPE}:Uyes} != "no" 158.endif # WFORMAT > 0 159.endif # WFORMAT 160.if defined(NO_WFORMAT) || defined(NO_WFORMAT.${COMPILER_TYPE}) 161CWARNFLAGS+= -Wno-format 162.endif # NO_WFORMAT || NO_WFORMAT.${COMPILER_TYPE} 163 164# GCC 165# We should clean up warnings produced with these flags. 166# They were originally added as a quick hack to enable gcc5/6. 167# The base system requires at least GCC 6.4, but some ports 168# use this file with older compilers. Request an exprun 169# before changing these. 170.if ${COMPILER_TYPE} == "gcc" 171# GCC 5.2.0 172.if ${COMPILER_VERSION} >= 50200 173CWARNFLAGS+= -Wno-error=address \ 174 -Wno-error=array-bounds \ 175 -Wno-error=attributes \ 176 -Wno-error=bool-compare \ 177 -Wno-error=cast-align \ 178 -Wno-error=clobbered \ 179 -Wno-error=deprecated-declarations \ 180 -Wno-error=enum-compare \ 181 -Wno-error=extra \ 182 -Wno-error=logical-not-parentheses \ 183 -Wno-error=strict-aliasing \ 184 -Wno-error=uninitialized \ 185 -Wno-error=unused-function \ 186 -Wno-error=unused-value 187.endif 188 189# GCC 6.1.0 190.if ${COMPILER_VERSION} >= 60100 191CWARNFLAGS+= -Wno-error=empty-body \ 192 -Wno-error=maybe-uninitialized \ 193 -Wno-error=nonnull-compare \ 194 -Wno-error=shift-negative-value \ 195 -Wno-error=tautological-compare \ 196 -Wno-error=unused-const-variable 197.endif 198 199# GCC 7.1.0 200.if ${COMPILER_VERSION} >= 70100 201CWARNFLAGS+= -Wno-error=bool-operation \ 202 -Wno-error=deprecated \ 203 -Wno-error=expansion-to-defined \ 204 -Wno-error=format-overflow \ 205 -Wno-error=format-truncation \ 206 -Wno-error=implicit-fallthrough \ 207 -Wno-error=int-in-bool-context \ 208 -Wno-error=memset-elt-size \ 209 -Wno-error=noexcept-type \ 210 -Wno-error=nonnull \ 211 -Wno-error=pointer-compare \ 212 -Wno-error=stringop-overflow 213.endif 214 215# GCC 8.1.0 216.if ${COMPILER_VERSION} >= 80100 217CWARNFLAGS+= -Wno-error=aggressive-loop-optimizations \ 218 -Wno-error=cast-function-type \ 219 -Wno-error=catch-value \ 220 -Wno-error=multistatement-macros \ 221 -Wno-error=restrict \ 222 -Wno-error=sizeof-pointer-memaccess \ 223 -Wno-error=stringop-truncation 224.endif 225 226# GCC 9.2.0 227.if ${COMPILER_VERSION} >= 90200 228.if ${MACHINE_ARCH} == "i386" 229CWARNFLAGS+= -Wno-error=overflow 230.endif 231.endif 232 233# GCC 12.1.0 234.if ${COMPILER_VERSION} >= 120100 235# These warnings are raised by headers in libc++ so are disabled 236# globally for all C++ 237CXXWARNFLAGS+= -Wno-literal-suffix \ 238 -Wno-error=unknown-pragmas 239.endif 240 241# GCC 13.1.0 242.if ${COMPILER_VERSION} >= 130100 243# These warnings are raised by headers in libc++ so are disabled 244# globally for all C++ 245CXXWARNFLAGS+= -Wno-dangling-reference 246.endif 247 248# GCC produces false positives for functions that switch on an 249# enum (GCC bug 87950) 250CWARNFLAGS+= -Wno-return-type 251 252# GCC's own arm_neon.h triggers various warnings 253.if ${MACHINE_CPUARCH} == "aarch64" 254CWARNFLAGS+= -Wno-system-headers 255.endif 256.endif # gcc 257 258# How to handle FreeBSD custom printf format specifiers. 259.if ${COMPILER_TYPE} == "clang" || \ 260 (${COMPILER_TYPE} == "gcc" && ${COMPILER_VERSION} >= 120100) 261FORMAT_EXTENSIONS= -D__printf__=__freebsd_kprintf__ 262.else 263FORMAT_EXTENSIONS= -fformat-extensions 264.endif 265 266.if defined(IGNORE_PRAGMA) 267CWARNFLAGS+= -Wno-unknown-pragmas 268.endif # IGNORE_PRAGMA 269 270# This warning is utter nonsense 271CFLAGS+= -Wno-format-zero-length 272 273.if ${COMPILER_TYPE} == "clang" 274# The headers provided by clang are incompatible with the FreeBSD headers. 275# If the version of clang is not one that has been patched to omit the 276# incompatible headers, we need to compile with -nobuiltininc and add the 277# resource dir to the end of the search paths. This ensures that headers such as 278# immintrin.h are still found but stddef.h, etc. are picked up from FreeBSD. 279# 280# XXX: This is a hack to support complete external installs of clang while 281# we work to synchronize our decleration guards with those in the clang tree. 282.if ${MK_CLANG_BOOTSTRAP:Uno} == "no" && \ 283 ${COMPILER_RESOURCE_DIR} != "unknown" && !defined(BOOTSTRAPPING) 284CFLAGS+=-nobuiltininc -idirafter ${COMPILER_RESOURCE_DIR}/include 285.endif 286.endif 287 288CLANG_OPT_SMALL= -mstack-alignment=8 -mllvm -inline-threshold=3 289.if ${COMPILER_VERSION} < 130000 290CLANG_OPT_SMALL+= -mllvm -simplifycfg-dup-ret 291.endif 292CLANG_OPT_SMALL+= -mllvm -enable-load-pre=false 293CFLAGS.clang+= -Qunused-arguments 294# The libc++ headers use c++11 extensions. These are normally silenced because 295# they are treated as system headers, but we explicitly disable that warning 296# suppression when building the base system to catch bugs in our headers. 297# Eventually we'll want to start building the base system C++ code as C++11, 298# but not yet. 299CXXFLAGS.clang+= -Wno-c++11-extensions 300 301# XXX This should be defaulted to 2 when WITH_SSP is in use after further 302# testing and soak time. 303FORTIFY_SOURCE?= 0 304.if ${MK_SSP} != "no" 305# Don't use -Wstack-protector as it breaks world with -Werror. 306SSP_CFLAGS?= -fstack-protector-strong 307CFLAGS+= ${SSP_CFLAGS} 308.endif # SSP 309.if ${FORTIFY_SOURCE} > 0 310CFLAGS+= -D_FORTIFY_SOURCE=${FORTIFY_SOURCE} 311CXXFLAGS+= -D_FORTIFY_SOURCE=${FORTIFY_SOURCE} 312.endif 313 314# Additional flags passed in CFLAGS and CXXFLAGS when MK_DEBUG_FILES is 315# enabled. 316DEBUG_FILES_CFLAGS?= -g -gz=zlib 317 318# Allow user-specified additional warning flags, plus compiler and file 319# specific flag overrides, unless we've overridden this... 320.if ${MK_WARNS} != "no" 321CFLAGS+= ${CWARNFLAGS:M*} ${CWARNFLAGS.${COMPILER_TYPE}} 322CFLAGS+= ${CWARNFLAGS.${.IMPSRC:T}} 323CXXFLAGS+= ${CXXWARNFLAGS:M*} ${CXXWARNFLAGS.${COMPILER_TYPE}} 324CXXFLAGS+= ${CXXWARNFLAGS.${.IMPSRC:T}} 325.endif 326 327CFLAGS+= ${CFLAGS.${COMPILER_TYPE}} 328CXXFLAGS+= ${CXXFLAGS.${COMPILER_TYPE}} 329 330AFLAGS+= ${AFLAGS.${.IMPSRC:T}} 331AFLAGS+= ${AFLAGS.${.TARGET:T}} 332ACFLAGS+= ${ACFLAGS.${.IMPSRC:T}} 333ACFLAGS+= ${ACFLAGS.${.TARGET:T}} 334CFLAGS+= ${CFLAGS.${.IMPSRC:T}} 335CXXFLAGS+= ${CXXFLAGS.${.IMPSRC:T}} 336 337LDFLAGS+= ${LDFLAGS.${LINKER_TYPE}} 338 339# Only allow .TARGET when not using PROGS as it has the same syntax 340# per PROG which is ambiguous with this syntax. This is only needed 341# for PROG_VARS vars. 342# 343# Some directories (currently just clang) also need to disable this since 344# CFLAGS.${COMPILER_TYPE}, CFLAGS.${.IMPSRC:T} and CFLAGS.${.TARGET:T} all live 345# in the same namespace, meaning that, for example, GCC builds of clang pick up 346# CFLAGS.clang via CFLAGS.${.TARGET:T} and thus try to pass Clang-specific 347# flags. Ideally the different sources of CFLAGS would be namespaced to avoid 348# collisions. 349.if !defined(_RECURSING_PROGS) && !defined(NO_TARGET_FLAGS) 350.if ${MK_WARNS} != "no" 351CFLAGS+= ${CWARNFLAGS.${.TARGET:T}} 352.endif 353CFLAGS+= ${CFLAGS.${.TARGET:T}} 354CXXFLAGS+= ${CXXFLAGS.${.TARGET:T}} 355LDFLAGS+= ${LDFLAGS.${.TARGET:T}} 356LDADD+= ${LDADD.${.TARGET:T}} 357LIBADD+= ${LIBADD.${.TARGET:T}} 358.endif 359 360.if defined(SRCTOP) 361# Prevent rebuilding during install to support read-only objdirs. 362.if ${.TARGETS:M*install*} == ${.TARGETS} && empty(.MAKE.MODE:Mmeta) 363CFLAGS+= ERROR-tried-to-rebuild-during-make-install 364.endif 365.endif 366 367# Please keep this if in sync with kern.mk 368.if ${LD} != "ld" && (${CC:[1]:H} != ${LD:[1]:H} || ${LD:[1]:T} != "ld") 369# Add -fuse-ld=${LD} if $LD is in a different directory or not called "ld". 370.if ${COMPILER_TYPE} == "clang" 371# Note: Clang does not like relative paths for ld so we map ld.lld -> lld. 372.if ${COMPILER_VERSION} >= 120000 373LDFLAGS+= --ld-path=${LD:[1]:S/^ld.//1W} 374.else 375LDFLAGS+= -fuse-ld=${LD:[1]:S/^ld.//1W} 376.endif 377.elif ${COMPILER_TYPE} == "gcc" 378# GCC does not support an absolute path for -fuse-ld so we just print this 379# warning instead and let the user add the required symlinks. 380# However, we can avoid this warning if -B is set appropriately (e.g. for 381# CROSS_TOOLCHAIN=...-gcc). 382.if !(${LD:[1]:T} == "ld" && ${CC:tw:M-B${LD:[1]:H}/}) 383.warning LD (${LD}) is not the default linker for ${CC} but -fuse-ld= is not supported 384.endif 385.endif 386.endif 387 388# Tell bmake not to mistake standard targets for things to be searched for 389# or expect to ever be up-to-date. 390PHONY_NOTMAIN = analyze afterdepend afterinstall all beforedepend beforeinstall \ 391 beforelinking build build-tools buildconfig buildfiles \ 392 buildincludes check checkdpadd clean cleandepend cleandir \ 393 cleanobj configure depend distclean distribute exe \ 394 files html includes install installconfig installdirs \ 395 installfiles installincludes lint obj objlink objs objwarn \ 396 realinstall tags whereobj 397 398# we don't want ${PROG} to be PHONY 399.PHONY: ${PHONY_NOTMAIN:N${PROG:U}} 400.NOTMAIN: ${PHONY_NOTMAIN:Nall} 401 402.if ${MK_STAGING} != "no" 403.if defined(_SKIP_BUILD) || (!make(all) && !make(clean*) && !make(*clean)) 404_SKIP_STAGING?= yes 405.endif 406.if ${_SKIP_STAGING:Uno} == "yes" 407staging stage_libs stage_files stage_as stage_links stage_symlinks: 408.else 409# allow targets like beforeinstall to be leveraged 410DESTDIR= ${STAGE_OBJTOP} 411.export DESTDIR 412 413.if target(beforeinstall) 414.if !empty(_LIBS) || (${MK_STAGING_PROG} != "no" && !defined(INTERNALPROG)) 415staging: beforeinstall 416.endif 417.endif 418 419# normally only libs and includes are staged 420.if ${MK_STAGING_PROG} != "no" && !defined(INTERNALPROG) 421STAGE_DIR.prog= ${STAGE_OBJTOP}${BINDIR} 422 423.if !empty(PROG) 424.if defined(PROGNAME) 425STAGE_AS_SETS+= prog 426STAGE_AS_${PROG}= ${PROGNAME} 427stage_as.prog: ${PROG} 428.else 429STAGE_SETS+= prog 430stage_files.prog: ${PROG} 431STAGE_TARGETS+= stage_files 432.endif 433.endif 434.endif 435 436.if !empty(_LIBS) && !defined(INTERNALLIB) 437.if defined(SHLIBDIR) && ${SHLIBDIR} != ${LIBDIR} && ${_LIBS:Uno:M*.so.*} != "" 438STAGE_SETS+= shlib 439STAGE_DIR.shlib= ${STAGE_OBJTOP}${SHLIBDIR} 440STAGE_FILES.shlib+= ${_LIBS:M*.so.*} 441stage_files.shlib: ${_LIBS:M*.so.*} 442.endif 443 444.if defined(SHLIB_LINK) && commands(${SHLIB_LINK:R}.ld) 445STAGE_AS_SETS+= ldscript 446STAGE_AS.ldscript+= ${SHLIB_LINK:R}.ld 447stage_as.ldscript: ${SHLIB_LINK:R}.ld 448STAGE_DIR.ldscript = ${STAGE_LIBDIR} 449STAGE_AS_${SHLIB_LINK:R}.ld:= ${SHLIB_LINK} 450NO_SHLIB_LINKS= 451.endif 452 453.if defined(STATIC_LDSCRIPT) && target(lib${LIB}.ald) 454STAGE_AS_SETS+= ald 455STAGE_DIR.ald = ${STAGE_LIBDIR} 456STAGE_AS.ald+= lib${LIB}.ald 457STAGE_AS_lib${LIB}.ald = lib${LIB}.a 458stage_as.ald: lib${LIB}.ald 459.endif 460 461.if target(stage_files.shlib) 462stage_libs: ${_LIBS} 463.if defined(DEBUG_FLAGS) && target(${SHLIB_NAME}.symbols) 464stage_files.shlib: ${SHLIB_NAME}.symbols 465.endif 466.else 467stage_libs: ${_LIBS} 468.endif 469.if defined(SHLIB_NAME) && defined(DEBUG_FLAGS) && target(${SHLIB_NAME}.symbols) 470stage_libs: ${SHLIB_NAME}.symbols 471.endif 472 473.endif 474 475.if !empty(INCS) || !empty(INCSGROUPS) && target(buildincludes) 476.if !defined(NO_BEFOREBUILD_INCLUDES) 477stage_includes: buildincludes 478beforebuild: stage_includes 479.endif 480.endif 481 482.for t in stage_libs stage_files stage_as 483.if target($t) 484STAGE_TARGETS+= $t 485.endif 486.endfor 487 488.if !empty(STAGE_AS_SETS) 489STAGE_TARGETS+= stage_as 490.endif 491 492.if !empty(STAGE_TARGETS) || (${MK_STAGING_PROG} != "no" && !defined(INTERNALPROG)) 493 494.if !empty(LINKS) 495STAGE_TARGETS+= stage_links 496.if ${MAKE_VERSION} < 20131001 497stage_links.links: ${_LIBS} ${PROG} 498.endif 499STAGE_SETS+= links 500STAGE_LINKS.links= ${LINKS} 501.endif 502 503.if !empty(SYMLINKS) 504STAGE_TARGETS+= stage_symlinks 505STAGE_SETS+= links 506STAGE_SYMLINKS.links= ${SYMLINKS} 507.endif 508 509.endif 510 511.include <meta.stage.mk> 512.endif 513.endif 514 515.if defined(META_TARGETS) 516.for _tgt in ${META_TARGETS} 517.if target(${_tgt}) 518${_tgt}: ${META_DEPS} 519.endif 520.endfor 521.endif 522 523# we are generally the last makefile read 524CFLAGS+= ${CFLAGS_LAST} 525CXXFLAGS+= ${CXXFLAGS_LAST} 526LDFLAGS+= ${LDFLAGS_LAST} 527