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Mic92Mic92
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Merge pull request #381 from crystax/master
Add --print-os-abi and --set-os-abi options
2 parents 7281d99 + 5faf453 commit 683e41d

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‎patchelf.1

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Original file line numberDiff line numberDiff line change
@@ -36,6 +36,16 @@ INTERPRETER.
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.IP --print-interpreter
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Prints the ELF interpreter of the executable.
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.IP --print-os-abi
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Prints the OS ABI of the executable (EI_OSABI field of an ELF file).
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.IP "--set-os-abi ABI"
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Changes the OS ABI of the executable (EI_OSABI field of an ELF file).
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The ABI parameter is pretty flexible. For example, you can specify it
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as a "Linux", "linux", or even "lInUx" - all those names will set EI_OSABI
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field of the ELF header to the value "3", which corresponds to Linux OS ABI.
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The same applies to other ABI names - System V, FreeBSD, Solaris, etc.
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.IP --print-soname
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Prints DT_SONAME entry of .dynamic section.
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Raises an error if DT_SONAME doesn't exist.

‎src/patchelf.cc

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Original file line numberDiff line numberDiff line change
@@ -86,6 +86,20 @@ static bool hasAllowedPrefix(const std::string & s, const std::vector<std::strin
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return std::any_of(allowedPrefixes.begin(), allowedPrefixes.end(), [&](const std::string & i) { return !s.compare(0, i.size(), i); });
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}
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static std::string trim(std::string s)
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{
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s.erase(s.begin(), std::find_if(s.begin(), s.end(), [](unsigned char ch) { return !std::isspace(ch); }));
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s.erase(std::find_if(s.rbegin(), s.rend(), [](unsigned char ch) { return !std::isspace(ch); }).base(), s.end());
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return s;
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}
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static std::string downcase(std::string s)
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{
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std::transform(s.begin(), s.end(), s.begin(), [](unsigned char c){ return std::tolower(c); });
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return s;
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}
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/* !!! G++ creates broken code if this function is inlined, don't know
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why... */
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template<ElfFileParams>
@@ -1104,6 +1118,68 @@ std::string ElfFile<ElfFileParamNames>::getInterpreter()
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return std::string((char *) fileContents->data() + rdi(shdr.sh_offset), rdi(shdr.sh_size) - 1);
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}
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template<ElfFileParams>
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void ElfFile<ElfFileParamNames>::modifyOsAbi(osAbiMode op, const std::string & newOsAbi)
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{
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unsigned char abi = hdr()->e_ident[EI_OSABI];
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if (op == printOsAbi) {
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switch (abi) {
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case 0: printf("System V\n"); break;
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case 1: printf("HP-UX\n"); break;
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case 2: printf("NetBSD\n"); break;
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case 3: printf("Linux\n"); break;
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case 4: printf("GNU Hurd\n"); break;
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case 6: printf("Solaris\n"); break;
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case 7: printf("AIX\n"); break;
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case 8: printf("IRIX\n"); break;
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case 9: printf("FreeBSD\n"); break;
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case 10: printf("Tru64\n"); break;
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case 12: printf("OpenBSD\n"); break;
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case 13: printf("OpenVMS\n"); break;
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default: printf("0x%02X\n", (unsigned int) abi);
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}
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return;
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}
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unsigned char newAbi;
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std::string nabi = downcase(trim(newOsAbi));
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if (nabi == "system v" || nabi == "system-v" || nabi == "sysv")
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newAbi = 0;
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else if (nabi == "hp-ux")
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newAbi = 1;
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else if (nabi == "netbsd")
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newAbi = 2;
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else if (nabi == "linux" || nabi == "gnu")
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newAbi = 3;
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else if (nabi == "gnu hurd" || nabi == "gnu-hurd" || nabi == "hurd")
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newAbi = 4;
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else if (nabi == "solaris")
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newAbi = 6;
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else if (nabi == "aix")
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newAbi = 7;
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else if (nabi == "irix")
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newAbi = 8;
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else if (nabi == "freebsd")
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newAbi = 9;
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else if (nabi == "tru64")
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newAbi = 10;
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else if (nabi == "openbsd")
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newAbi = 12;
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else if (nabi == "openvms")
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newAbi = 13;
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else
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error("unrecognized OS ABI");
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if (newAbi == abi) {
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debug("current and requested OS ABIs are equal\n");
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return;
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}
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hdr()->e_ident[EI_OSABI] = newAbi;
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changed = true;
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}
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template<ElfFileParams>
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void ElfFile<ElfFileParamNames>::modifySoname(sonameMode op, const std::string & newSoname)
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{
@@ -1739,6 +1815,9 @@ void ElfFile<ElfFileParamNames>::clearSymbolVersions(const std::set<std::string>
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}
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static bool printInterpreter = false;
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static bool printOsAbi = false;
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static bool setOsAbi = false;
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static std::string newOsAbi;
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static bool printSoname = false;
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static bool setSoname = false;
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static std::string newSoname;
@@ -1764,6 +1843,12 @@ static void patchElf2(ElfFile && elfFile, const FileContents & fileContents, con
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if (printInterpreter)
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printf("%s\n", elfFile.getInterpreter().c_str());
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if (printOsAbi)
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elfFile.modifyOsAbi(elfFile.printOsAbi, "");
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if (setOsAbi)
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elfFile.modifyOsAbi(elfFile.replaceOsAbi, newOsAbi);
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if (printSoname)
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elfFile.modifySoname(elfFile.printSoname, "");
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@@ -1839,6 +1924,8 @@ void showHelp(const std::string & progName)
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[--set-interpreter FILENAME]\n\
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[--page-size SIZE]\n\
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[--print-interpreter]\n\
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[--print-os-abi]\t\tPrints 'EI_OSABI' field of ELF header\n\
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[--set-os-abi ABI]\t\tSets 'EI_OSABI' field of ELF header to ABI.\n\
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[--print-soname]\t\tPrints 'DT_SONAME' entry of .dynamic section. Raises an error if DT_SONAME doesn't exist\n\
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[--set-soname SONAME]\t\tSets 'DT_SONAME' entry to SONAME.\n\
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[--set-rpath RPATH]\n\
@@ -1888,6 +1975,14 @@ int mainWrapped(int argc, char * * argv)
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else if (arg == "--print-interpreter") {
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printInterpreter = true;
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}
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else if (arg == "--print-os-abi") {
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printOsAbi = true;
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}
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else if (arg == "--set-os-abi") {
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if (++i == argc) error("missing argument");
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setOsAbi = true;
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newOsAbi = resolveArgument(argv[i]);
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}
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else if (arg == "--print-soname") {
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printSoname = true;
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}

‎src/patchelf.h

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Original file line numberDiff line numberDiff line change
@@ -109,6 +109,10 @@ class ElfFile
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110110
std::string getInterpreter();
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typedef enum { printOsAbi, replaceOsAbi } osAbiMode;
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void modifyOsAbi(osAbiMode op, const std::string & newOsAbi);
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typedef enum { printSoname, replaceSoname } sonameMode;
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void modifySoname(sonameMode op, const std::string & newSoname);

‎tests/Makefile.am

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@@ -33,6 +33,7 @@ src_TESTS = \
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endianness.sh \
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contiguous-note-sections.sh \
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no-gnu-hash.sh \
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change-abi.sh \
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grow-file.sh \
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no-dynamic-section.sh \
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args-from-file.sh \

‎tests/change-abi.sh

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@@ -0,0 +1,44 @@
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#! /bin/sh -e
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SCRATCH=scratch/$(basename $0 .sh)
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rm -rf ${SCRATCH}
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mkdir -p ${SCRATCH}
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cp simple-pie ${SCRATCH}/simple-pie
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# Save the old OS ABI
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OLDABI=`../src/patchelf --print-os-abi ${SCRATCH}/simple-pie`
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# Ensure it's not empty
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test -n "$OLDABI"
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# Change OS ABI and verify it has been changed
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{
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echo "System V"
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echo "HP-UX"
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echo "NetBSD"
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echo "Linux"
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echo "GNU Hurd"
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echo "Solaris"
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echo "AIX"
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echo "IRIX"
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echo "FreeBSD"
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echo "Tru64"
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echo "OpenBSD"
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echo "OpenVMS"
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} | {
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while IFS="\n" read ABI; do
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echo "Set OS ABI to '$ABI'..."
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../src/patchelf --set-os-abi "$ABI" ${SCRATCH}/simple-pie
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echo "Check is OS ABI is '$ABI'..."
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NEWABI=`../src/patchelf --print-os-abi ${SCRATCH}/simple-pie`
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test "$NEWABI" = "$ABI"
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done
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}
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# Reset OS ABI to the saved one
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../src/patchelf --set-os-abi "$OLDABI" ${SCRATCH}/simple-pie
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# Verify we still can run the executable
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${SCRATCH}/simple-pie

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